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Henrik Bj2jegh

HANDBOOK

OF

NON-TOXIC INTAGLIO ACRYLIC RESISTS PHOTOPOLYMER FILM & SOLAR PLATES ETCHING

B

0 E G H

Henrik B0egh

HANDBOOK

OF

NON-TOXIC INTAGLIO ACRYLIC RESISTS PHOTOPOLYMER FILM & SOLAR PLATES ETCHING

B 0 E G H

Also publishedby the author: The video programme and compendium: ,,NON-TOXIC INTAGLIO STEP BY STEP"

The videotapeillustratesall the workingprocessesdescribed in this book.The video lasts 60 minutesand is availablein all VHS systems (PAL, NTSC, SECAM). The videotape is accompaniedby a compendiumdescribingall the processes step by step. The compendiumcontains24 pages. ,,This is a well compiled video that explains the non-toxic process and technique thoroughly and in detail. The Grafisk Eksperimentarium has worked hard to iron out most of the problems that past users have found with this process. This is the ,,must have" video for people who wish to take up this printmaking method." Steve Hoskins in Printmaking Today spring 2001 ,,In a calm, clarified flow, the video demonstrates the non-toxic process step by step. The thorough division into sequences makes it easy to find one's way through the various techniques and, if needed, rewind. The enclosed compendium is a good supplement to the video and in itself a pedagogical tool that can stand alone. In our effort to disseminate and teach the new health- and environmentfriendly working processes, we welcome this new set of tools. Finn Naur Petersen (senior lecturer at the Royal Danish Academy of Fine Art), in BKF-Bladet, Aug. 2000.

Copyright by Photos/illustrations Layout and DTP Printed by Frontpage artwork Translation

Henrik B0egh and Forlaget B0egh Henrik B0egh where nobody else is mentioned Henrik B0egh and Ase H0jer Narayana Press, Gylling - DK Toner Washing by Henrik B0egh Helene Bengtson Printed in Denmark 2003 First edition, first printing

ISBN 87-987757-2-3

Order the book from:

FORLAGET B0EGH (The Printmakers' Experimentarium)

Trepkasgade 8, DK-2100 Copenhagen Tel. (+45) 3535 3907 I Fax (+45) 3536 3821 All rights reserved. Ne part ef this publ!catien may be repreduced er e/ectrenic ferm witheut permission from the copyright holder.

111anv

matenal

E-mail: [email protected]. www.GrafiskEksperimentarium.dk

PREFACE Appendix l:TheTransition to the Non-Toxic Studio This appendix addresses those who wish to change or expand already existing printmaking studios so as to apply the new techniques. Appendix II: Digital Imaging Here I address printmakers and others who are inexperienced in digital imaging but who wish to prepare computer-generated stencils for photopolymer gravure and etchings. Appendix Ill: Printing This appendix addresses photographers and others who wish to make their own prints without having any experience beforehand. The Printmakers' Experimentarium The Printmakers' Experimentarium was established in Copenhagen by the author in 1996 with the following aims:

This is a handbook of Non-Toxic Intaglio. The book can be read in its entirety and thus provide a survey of the subject, but it is also able to serve as a reference book with easily found solutions to specific problems. All working processes in connection with the application and use of acrylic resists, photopolymer film, solar plates and etching have been thoroughly described and illustrated. At the back of the book there is a user-friendly index and a list of materials and litterature. Content and Target Group The primary content of the book has been written with professional printmakers in mind. That goes for the main chapters:

Acrylic Resists Etching Photopolymer Film and Solar Plates As we are, however, moving in fairly uncharted territories, the target group will hopefully be much wider. Therefore, I have chosen to add three supplementary appendices:

• • •

•

Testing and evaluating new printmaking techniques and materials based on acrylics and polymers Imparting experience with such techniques and materials to the art schools and creative artists Arranging workshops, conferences and demonstrations of Non-Toxic Printmaking Advising schools and graphics workshops on establishing and equipping Non-Toxic Studios

The motivation was found in the fact that the materials which had previously been used contained a veritable cocktail of acids and chemicals, the danger of which was without parallel anywhere else in the creative arts. The new acrylic resist etching system and the use of photopolymer film were introduced as late as the mid 1990s, or approximately five hundred years after the invention of intaglio printing. The development of these new printing materials, which are supposed to be harmless to the health and environment if used correctly, was

pioneered by visionary people like Keith Howard, Mike Zafron, Friedhard Kiekeben, Robert Adam and othets in the mid 1990s - to whom we can all be thankful today. The Situation Today Much has happened since then, and we now have a complete non-toxic alternative to every process in conventional intaglio. In addition, the introduction of new materials and processes has given us a number of fresh means of expression, which were impossible in conventional intaglio.

Throughout my entire research in this field, it has been my clear objective to limit the materials to the lowest possible number with the highest possible efficiency. I have also striven to create practical and affordable solutions to the problem of finding the necessary equipment for the various processes - and needless to say, these solutions have had to meet the very strictest demands of the professional printmaker. Another crucial objective for me has been to stay clear of affiliation with particular manufacturers or products. The Printmakers' Experimentarium remains completely independent of financial or other kinds of stakes potentially held by the industry. The products mentioned in this book have been chosen on the grounds of just two criteria: They must have a stamp of approval from the relevant authorities as regards health and environment, and they must meet the professional printmaker's demands in relation to the work of art which is the all-important end-product. If or when new and better materials are developed, the necessary information will be made available on our website: www.artbag.dk (look for The Printmakers' Experimentarium). In 1999 I published the video ,,Non-Toxic Intaglio Step by Step'; and I have sincethen been encouragedby printmakers all over the world to publish a handbook. With the present publication, I hope to have honoured this request. Henrik Beegh, May 2003

All prints have been made at The Printmakers' Experimentarium except the one on page 75 left which has been made at The Canadian School for Non-Toxic Printmaking.

CONTENTS

INTRODUCTION Toxicity in Traditional Etching The Chemistry of Acrylics

9

10

PLATE PREPARATION General Remarks Sanding and Polishing De-Greasing Summary Materials

13 13 13 14 14

ACRYLIC RESISTS

15

LIQUID HARD GROUND General Remarks Applying the Hard Ground Transparent vs. Black Hard Ground Working in the Hard Ground Stopping Out Removing the Etching Grounds Summary Materials

16 16 17 17 17 17 19 19

ROLL-ON SOFT AND HARD GROUND General Remarks Applying the Etching Ground Roll-on Soft Ground Soft Ground Drawings Soft Ground Impressions Roll-On Hard Ground Other Options Stopping Out Removing the Etching Grounds Summary Materials

23 23

SPRAYED AQUATINT General Remarks Applying the Aquatint Uniform Aquatint Modulated Aquatint Other Options Stopping Out Removing the Aquatint and the Stop-Out Summary Materials

24 24 25 26 26 27 27 28 28

20 20 21 21 21 21 22 22 22

LIFT GROUNDS General Remarks 31 Lift Ground Using Oil and Water 31 Removing the Etching Ground 31 31 Summary 31 Materials Reversed Lift Ground 32 Lift Ground Using Photopolymer Film 32 Removing the Photopolymer Film and Aquatint 32 33 Materials WASHINGS AS ACRYLIC RESISTS General Remarks Soft Ground Washings Applying the Wash Media Removing the Wash Media ..Summary

34 34 34

35 35

Materials White Ground General Remarks Preparing the White Ground Applying the White Ground Applying White Ground to an Etched Plate Removing the White Ground Summary Materials

35 36 36 36 36 37 37 37 37

COLLOGRAPH TECHNIQUES Materials

38

ETCHING - BACKING AND STRIPPING

39

General Remarks Etching Copper in Ferric Chloride Etching in Tanks Etching in Open Trays Disposal Safety Etching Zinc with the Bordeaux Etch Etching the Zinc Plate Disposal Safety

40 41 41 41 42 42

43 43 43 43

BEFORE, DURING AND AFTER ETCHING Backing the Plate De-Oxydizing Removing the Etching Grounds

44 44 44

PHOTOPOLYMER FILM AND SOLAR PLATES

45

General Remarks What Is Photopolymer? Photopolymer Film Two Techniques PHOTOPOLYMER FILM - FOR NON-ETCHINGS The Positives on Transparent Film 1. The Line Drawing 2. The Halftone 3. The Continuous Tone

46 47 47 47

48 48 48 49

Laminating the Plate Lamination Solution Preparing the Developer Safety Calibrating Positives to the Exposure Unit 1 . Calibration of the Line Drawing 2. Calibration of the Halftone Sources of Error 3a. Calibration of the Aquatint Screen 3b.Calibration of the Continuous Tone Adjusting Contrast - Flash Exposure

50 50 51 51 52 52 52

53 53 54 55

PHOTOPOLYMER FILM - FOR ETCHINGS General Remarks Thinning the Photopolymer Film The Subject for Etching The Black and White Drawing/Washing The Halftone (Photogravure) Removing the Etching Ground Safety

57 58 58 58 59 59 59

PHOTOPOLYMER PLATES-SOLAR General Remarks Handling the Plates Cutting the Plates Before Exposure UV Exposure Development and Drying Hardening Safety

61 61 61 61 62 62 62 62

CREATING THE POSITIVES Drawing and Washing Techniques Drawing and Washing Media Toner Washings UV Exposure Digitally Generated Stencils General Remarks The Printer Printing the Halftone Printing the Continuous Tone Other Options and Effects Multiple Layers of Photopolymer

PLATES

65 65 65 66 68 68 68

Film

69 70 72 72

Two Layers of Photopolymer Film Drawing and Relief Several Layers of Photopolymer Film Laminating onto an Etched Plate Laminating onto Other Materials Sunlight Exposure Create Effect for Effect Wrinkled Images Collage

72 73 73 73 73 74 75 75 75

PHOTOCOPYTRANSFER General Remarks

77

APPENDIX I The Transition to the Non-Toxic Studio

79

General Remarks - 0.1.Y. Drying Cabinet, Aquaint Cabinet, UV-Exposure Cabinet - Vacuum Frame - Developer Container - Light Table - Sinks and Containers - Etching Tank

APPENDIX II Scanning and Digital Imaging

85

General Remarks - The Kodak Photo CD - The Film Scanner - The Perfect Negative for Photogravure The Flatbed Scanner - Digital Imaging: Open Image Change Mode - The Crop Tools - Levels Ajustments The Healing Brush - Save as Master Image - File Format - Image Size - Sharpen Image

APPENDIX Ill Intaglio Printing

99

Preparing the Printing Paper - Preparing the Etching Ink - Inking the Plate - Wiping the Plate - Printing - Finishing Treatments

BIBLIOGRAPHY

104

INDEX

104

RECOMMENDED MATERIALS

104

Open Letter to a Sceptic Nothing in this world is Non-Toxic, neither the air we breathe, the food we eat, the medicine the doctors prescribe or the materials mentioned in this book. Toxicity is a relative term. When despite of this I have still chosen the title ,,Handbook in Non-Toxic Intaglio", it is because the ,,baby" was already named ,,Non-Toxic"at its birth in the mid-1990s. Furthermore, the authorities officially use the designation ,,AP Non-Toxic".Thus ,,Non-ToxicPrintmaking" today is a concept or trade description covering a range of health and environment-friendly working methods which all printmakers have at least heard of - hence the title ,,Handbook in Non-Toxic Intaglio". Although the book should rightfully be called ,,Handbook in Less-Toxic Intaglio", I like the name ,,Non-ToxicPrintmaking" nonetheless, the reason being that this apparent provocation has occasioned a sometimes hot debate between its adherents and opponents and created a focus on what we do as printmakers, what we do not do, and what we should be doing. For 500 years, nobody has questioned the materials and methods used by printmakers. It was not until the launch of these new techniques that the consideration we must show ourselves, each other and the environment became an issue. Today, no sensible human beings can defend working on with the conventional methods and materials, not eventhe schools, where safety and exhaust systems are state of the art - because what will Eve do when she has completed her education, which has only taught her the toxic methods, and she cannot afford the necessary safety equipment? We all know that this is not an individual choice, but a common responsibility, to the person standing next to you as well as to the environment in general, and we all know that ,,Non-Toxic"or ,,Less-Toxic" printmaking is the future. Let us appreciate that and continue a healthy debate. But let us not forget to make some art - at the end of the day, that is what inspires us to a better life; not only spiritually, but, as the pursuit of art makes us push boundaries and develop new, healthier techniques, hopefully this better life will be physical as well. Henrik B0egh

INTRODUCTION

The overall motivational factor for the development of the techniques and working methods described in this book has of course been the threats to health and environment posed by the technology of conventional intaglio. If art schools and printmaking studios were to live up to the rules and regulations pertaining to the (working) environment of the graphic industry, the cost of the necessary equipment for safety and ventilation would be too much for the individual school or studio to bear and thus inevitably close some of them down. In addition to this, the chemicals used would still be present in the studios as potential risk factors. All conventional acid-resistant grounds have safer acrylic alternatives. Among the acrylic resists there are products and processes to match any conventional technique and quality, such as hard ground, soft ground, aquatint, photogravure, etc. Furthermore, the new techniques and materials have given rise to several possibilities that have not even been named yet, as they simply did not exist within the realm of the oil-based grounds. In consequence of their strength and durability, many of the acrylic resists

can also be used for relief printing, either alone or in combination with etching techniques. Concurrently, the use of photopolymer film for circuit boards in the electronic industry has made it feasible to integrate photography and digital images in traditional modes of graphic expression. It should therefore be underlined from the beginning how erroneous it would be to regard the new acrylic-based techniques merely as substitutes for the old ,,toxic" methods and materials. What we are dealing with is an epoch-making discovery, which not only holds the solution to the serious consequences to health and environment implied by conventional processes, but which also creates a whole new set of possibilities thus far virtually unknown to intaglio printmaking. Toxicity in Traditional Etching It is a well-established fact that conventional materials for intaglio printmaking contain quite a cocktail of acids and chemicals, the danger of which is unmatched in the creative arts. Each of them may have damaging effects 9

on the health of the artists and on the surrounding environment, but in combination they pose a very serious threat to anyone who uses them with some frequency. The conventional materials are mainly oil-based, and most of the resists have arisen from the petrochemical industry. That applies to e.g. asphaltum varnishes, shellac, mixtures of tar and wax, resins and the like. Several of these products have been found to provoke cancer, and also to contain organic solvents constantly generating toxic fumes that rapidly permeate the indoor climate of the studio. Brief exposure to these solvents cause headache and nausea, while frequent use over an extended period of time typically cause damages to the liver, kidneys, or nervous system. But organic solvents are not only a part of the contents of oil-based varnishes; they are often in constant use in conventional printmaking studios for cleaning plates and tools. In consequence of their volatile nature they are easily absorbed into our blood via inhalation and skin contact. The safety regulations pertaining to the use of these chemicals in the industry are, not unreasonably, among the very strictest. The use 10

of nitric acid, which is typical of printmaking studios, is not only unnecessary; it is positively deadly. In the industry, nitric acid is restricted to be used only in hermetically sealed boxes with welded-on rubber gloves; the same kind that is necessary in connection with radioactive substances. The generation of toxic fumes during the etching process may cause impotence, sterility, and foetal damage. The use of Dutch mordants, plate smoking etc. likewise poses serious health threats. The method of using hot plates to heat the conventional etching inks (which contain solvents) constitutes another unnecessary source of exposure to the toxic fumes and of their transmission to the general indoor climate. The Chemistry of Acrylics All acrylic resists consist of acrylic and polymer substances in a more or less liquid form and contain water as solvent. They acquire the qualities that make them suitable for intaglio during the drying and hardening process:The separate polymer particles, which constitute the watery emulsion while the resists are fluid, begin to

bind as the water evaporates. Eventually they will be bound solidly together in a long, single polymer chain, thus creating a very tough substance which is durable as well as completely acid resistant. Acrylics that have been brushed, poured or sprayed onto a clean plate bind so tightly to the surface of the plate that the ferric chloride will not be able to work its way under the metal along the , eroded edges. If necessary, the acrylic coating may remain on the plate during the printing process. As long as acrylics are fluid, they can easily be cleansed off brushes and surfaces with soapy water, but they become waterproof when fully hardened. Dry acrylic remnants can be removed in a solution of washing soda and water.

acquired. In many cases they are manufactured for completely different purposes, e.g. domestic use. Consequently, they are often much cheaper than the products conventionally employed by printmakers. Our website contains updated Safety Data Sheets for all the products used.

Many acrylics dry very quickly, but the drying and hardening period can be further shortened with the use of a drying cabinet. This method also adds to the durability. When one needs to clean a plate, it is placed in a photo tray containing washing soda and water. The etching grounds are easy to prepare for their intended purpose, and the necessary ingredients are easily 11

The acrylic etching grounds - here are all the materials you need.

PLATE PREPARATION

General Remarks Whether one uses copper, zinc, steel, or other plates for etching, the plate must be carefully de-greased before applying the etching ground. Many countries have a longstanding tradition of etching in zinc. This might cause surprise, as zinc, compared to copper, is soft and an inferior metal for intaglio printing. Consequently, these etchings do not appear as clean and precise as they would in copper.

The assumption of this book, however, is that nothing but hard 0.5mm/0.2 inch copper or thicker is used. Zinc plates are somewhat soft and must therefore necessarily be as thick as 0.8 mm or more for etchings. That does not apply to copper, which is a harder metal, rendering 0.5 mm plates fully sufficient. 0.5 mm copper is normally cheaper than 0.8 mm zink. As it is nevertheless a wellknown fact that some printmakers prefer zinc for aesthetic reasons, the working methods pertaining to zinc plates will be dealt with wherever they might differ from those regarding copper. In all other cases, the working process is the same whether zinc or copper is used.

Sanding and Polishing Before applying the etching ground or laminating the photopolymer film onto the plate, any scratches in the plate must be removed. The plate is sanded down with sand paper P1200 Wetordry. I recommend giving the plate a thin spray of water from an atomizer before sanding, so as to avoid metal dust in the room. Working gloves are recommendable, protecting your skin from tiny intruding metal splinters. Further polishing may be carried out with chalk powder and water using a polish-sponge. De-Greasing Finally, the plate must be de-greased. The most important difference between preparing plates for conventional oilbased etching grounds and preparing those for acrylicbased grounds is that the acrylic resists require a completely de-greased printing plate if they are to adhere - otherwise there is a risk that the etching grounds will break up during the etching process.

Needless to say, one must not touch the plate with one's fingers. Clean the copper plate thoroughly with scouring 13

cream. Then rinse and wash the plate with a sponge and some de-greaser. Wear rubber gloves in order to ~void leaving greasy marks on the plate. After the final rinse, dab off the water with an old newspaper and a dry dishtowel. Finally leave the plate in the drying cabinet for a few minutes (seep. 80). Now the plate is ready for the application of the etching ground or photopolymer film. Remember to use rubber gloves throughout the de-greasing process to avoid touching the de-greased plate with your bare hands. Fingerprints may cause the etching ground not to stick or the photopolymer film to loosen after it has been laminated. Polishing and degreasing of the copper plate .

Summary

2 3 4 5 6 7 8 9

Remove any scratches in the copper plate with fine sandpaper or steel wool. Rinse the plate in running water. Clean and polish the plate thoroughly with chalk powder and water using a polish-sponge. Rinse the plate in running water. Clean the plate thoroughly with scouring cream and rinse the plate in running water. Wash the plate with a clean sponge and de-greaser. Rinse the plate in running water. Dab off the water with an old newspaper. Dry the plate in the drying cabinet (see p. 80). PS. Acrylic resists and photopolymer film require a completely de-greased copper plate if they are to adhere to the plate.

14

Drying cabinet (see D.I. Y. instructions p. 80)

Materials Steel wool and/or sandpaper P1200 WetorDry Chalk powder (Alternative : Magnesium Carbonate) Sponge Scotch-Brite Scouring Cream CPS de-greaser cone. - mix with water 1: 12 (Alternative: Dawn dish detergent - only in the USA. Or vinegar and water.)

ACRYLIC RESISTS

LIQUID HARD GROUND

pour on a liberal amount of the hard ground in one go. Distribute it quickly, before it has time to harden , and immediately afterwards place it in vertical position on a newspaper to let the excess polish run off. The hard ground that has run into the photo tray may be poured back into the bottle. Move the plate a few times on the newspaper to prevent the hard ground from building up along the lower edge. A thin, even coat of hard ground is essential , as it will otherwise break up when etched . After a few minutes on the newspaper, the plate is ready to be hardened in the drying cabinet (see page 80) . After 1O minutes of hardening , the surface is ready to be worked. Do not shake the bottle before applying the hard ground due to the risk of creating bubbles in the liquid!

General Remarks As hard ground we use an acrylic floor polish. The liquid hard ground is extremely strong , and the plate can be wiped and printed while the hard ground is still on. You can work in the acrylic hard ground in exactly the same way as in the conventional hard ground . But you also have the option of doing washings in the hard ground with a mild solution of ammonia and water. It also complies with another decisive requirement for hard grounds, which is the option of making several etchings and overlapping cross-hatchings without having them ruined in the intersecting lines. This hard ground dries very quickly and will preserve the particular imprint of the employed drawing utensils , which may range from those leaving only the thinnest lines to the ones biting deeply into the surface . Applying the Hard Ground Prepare and de-grease the copper plate and pour the liquid hard ground directly onto it, holding it above a photo tray. When holding the copper plate, one's fingers must remain under it (the way a waiter carries a tray) - and remember to use rubber gloves. Hold the plate above the tray and 16

On a copper plate , the hard ground will now be ready for use . A zinc plate will require another thin coat of floor polish as described above with a drying period of five to ten minutes, after which process the plate will be ready. After pouring the excess polish back into the bottle, clean the tray in water .

I

The hard ground is poured onto the plate in one go, and immediately afterwards it must be placed in vertical position on a newspaper to let the excess polish run off.

Hard ground line drawing printed with the hard ground on (left) and the same plate printed without the hard ground (right) - the only difference is in the plate tone. Artwork: Mikael Larsen. Not even the finest cross-hatchings will break up during the etching process (right). Artwork: Terje Risberg.

Transparent vs. Black Hard Ground The liquid hard ground in itself forms a completely clear (transparent) surface, but if you prefer a black surface , it can also be made completely black like the old-fashioned smoked plate by painting or spraying it with diluted black gouache. Before etching , remove the ink layer with a soft sponge with lukewarm water and detergent in order not to spoil the ferric chloride. The black surface enables the artist to see his or her drawings clearly. However, the advantage to transparent hard ground is that it can easily be applied to already etched surfaces with a view to adding more lines or hatchings. The already etched lines or areas are thus visible underneath during the process of drawing, hatching or otherwise working on the plate. Working in the Hard Ground You can work in the acrylic-based hard ground in exactly the same way as in a conventional hard ground. It does, however, offer the option of doing washings in the hard ground wild a mild solution of ammonia and water (Ajax Window Cleanset') or soda and water. This technique opens up areas of the plate like a direct lift ground of

sorts. The areas can then be etched , either as open bites or with an addition of aquatint. Stopping Out If one wants to stop out an area, it can be painted over with a coat of Acrylic Stop-Out Varnish and left in the drying cabinet for five minutes, after which the etching can be reassumed. If the areas in question are large or have bold lines in them, it is recommendable to de-oxidize the plate before stopping out (seep . 44). Removing the Etching Ground When the etching of the plate has been completed, the hard ground can either be left on or removed . The advantage of leaving it on consists partly in the possibility of continuing to work in the hard ground, partly in the fact that it makes the plate easier to wipe. A possible disadvantage could be that the hard ground leaves no plate tone on the print - the background is left completely white . So, if a plate tone is preferred , simply remove the hard ground in a solution of soda and water (as described on p. 44). 17

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Top left: Three kinds of sand paper pressed into the etching ground in the etching press + hatchings. Etched 20 mins in tank. Artwork : Gunnar Nielsen. Top right: Line drawings etched and stopped out after 15 mins, one hour and three hours, respectively. Artwork Gunnar Nielsen. Bottom right: Line Drawing and open bite etched 30 mins in tank.

18

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Hold the plate above a tray and pour on a liberal amount of hard ground in one go. Distribute it quickly, before it has time to harden, and place it in vertical position on a newspaper to let the excess polish run off. Move the plate a few times on the newspaper to prevent the hard ground from building up along the lower edge. After a few minutes on the newspaper, the plate is ready to be hardened in the drying cabinet for approximately 10 minutes. If you are applying the hard ground to an already etched plate, you must now repeat the above four stages. If it has not been etched beforehand, you are ready to work in the plate.

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If you prefer a black surface, paint it over with diluted black gouache or spray it on with an airbrush. For brushing dilute 1 part gouache with 1 part demineralised water. For spraying dilute with 2-3 parts water. The gouache dries in a couple of minutes in the drying cabinet. The black coat should be removed with lukewarm water and detergent before etching so that it will not ruin the ferric chloride.

C Liquid hard ground etched for 3 hours. Stripped, applied aquatint and painted with a mixture of Edinburgh Etch and wallpaper glue (spit bite). Compare the lines in this hard ground with the roll-on hard ground on page 20 - the needle used is the same and etching time is the same. Artwork : Peter Martensen .

MPterials Hard ground : Johnson Klear Polish (Alternative: Future Floor Polish in the USA or Z-Acryl Hardground) Washing : Ammonia and water (Ajax Window Cleanser) or soda and water Black Colour : Black Gouache + water Stop Out: Golden Acrylic Stop Out Varnish

19

ROLL-ON SOFT GROUND AND HARD GROUND 'I

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General Remarks When making soft ground etchings, the technique is to give the plate a surface which is sufficiently impressionable to render in the intaglio even the finest imprints of the objects pressed against the plate. As is the case with the traditional wax-based soft ground, one can make drawings in the acrylic-based soft ground (e.g. using a soft pencil on a piece of newspaper or a ballpoint pen on sandwich paper, resting one's wrist on a block of wood) . It is also possible to transfer patterns and textures from various objects to the soft ground.

The acrylic-based etching ground system offers a unique possibility of combining soft and hard grounds.The etching ground consists of water based ink for block prints mixed with an acrylic binder. Applying the Etching Ground Prepare and de-grease the plate. Mix the binder and the ink thoroughly on a glass plate. The amount of binder mixed into the ink determines the time required for hardening and drying. For fast-drying soft and hard

20

---..

-

-.....

grounds the mixture contains 1/3 binder and 2/3 ink, which will harden after approximately 20 minutes in the drying cabinet. Without the binder, the etching ground takes five hours to harden. The result after mixing must be a thick, even substance which does not curdle. Now roll the etching ground evenly onto the glass plate by means of a roller; first as a relatively thick layer, which is used as a reservoir , then as a thin, dry layer. From the glass plate roll the etching ground onto the copper plate from all sides and in thin coats. A glimpse of copper should be visible through the translucent surface. The plate can now be used as a soft ground, or it can be hardened to a hard ground.The ink roller must be cleaned immediately after use with a soft sponge and lukewarm water with dishwashing detergent. Sketch for the artwork on page 19 - here rolled-on hardground etched for 3 hours. Compare the lines in this hardground with those of the liquid hard ground on page 19. Artwork: Peter Martensen.

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Left:The etching ground is rolled onto the copper plate from all sides and in thin coats. Right: Soft ground impression etched one hour.

Roll-On Soft Ground If you want a soft ground , leave the plate with the wet ground in room temperature for 1O to 15 minutes just enough to dry its surface a little. It will then be suitable for draw-through soft ground or soft ground impressions. Soft Ground Drawings Soft ground drawings can be made on a sheet of soft paper which absorbs the ink. You can also paint directly into the soft ground with demineralised water , or you can use various drawing requisites directly in the soft ground. The soft ground starts drying after approximately one hour - if you need more time for your artwork , use less or no binder. Without binder you can work four hours in the soft ground in this ,,draw-through" technique . After finishing :

•

if binder is added leave the plate for 20 minutes in the drying cabinet and it becomes a hard ground , which can either be worked further or etched right away.

•

if no binder is used leave the plate to air-dry overnight and it becomes a hard ground which can either be worked further or etched right away.

Soft Ground Impressions Of course, you can press various objects and structures into the soft ground. The newly rolled-on soft ground must be left in room temperature for 10 to 15 minutes before the surface is ready to receive these imprints.

When the objects are in place on top of the soft ground and the plate has been placed on the etching press bed, take a piece of thin plastic foil , e.g. the inside protection foil or mylar that we take off the photopolymer film when laminating the film onto the plate , and coat the foil evenly with salad oil. Then place it (oily side down) on the plate and the objects. Because oil repels water, the plastic foil will not stick to the soft ground. Finally cover the whole thing with a piece of thin pasteboard without structure in order to avoid the litte holes made by the felt on the etching press in the final print. 21

Other Options - Washings It is feasible to dissolve the unhardened soft ground relief ink with demineralised water and paint it onto the copper plate, as if it were watercolour. In this way, washing will be endowed with the same possibilities as lithography. The solution can also be rolled on and diluted locally with a brush or cotton bud. The painted motif must then be left to dry (harden) completely before the plate is etched . This technique is also combinable with soft and hard ground as described above. For instance, try dissolving the rolled-on soft ground by painting it with water in local areas of the plate while treating other areas as soft ground, perhaps adding lines with hard ground tools after the hardening.

The pressure on the press must be reduced in proportion with the height of the objects on the plate. Run the plate through the press. Remove the pasteboard first , then carefully pull off the plastic. If the ink sticks to the foil , it is because there is not enough oil on it. Finally remove the objects gently and harden the plate for 20 minutes in the drying cabinet. The soft ground now becomes a hard ground , which can either be worked further with various drawing tools or etched right away. The ground is strong enough to be etched to any depth. Roll-On Hard Ground After 20 minutes of hardening , the roll-on soft ground becomes a hard ground. Because of the hardening , the plate can now be removed from the etching tray or tank, rinsed in water, inspected , stopped out and etched some more. When the hard ground has dried up, it is soluble in a mild solution of ammonia and water or soda and water. This solution can be used locally for washings carried out with a cotton bud or a brush. The amount of binder determines the time it takes for the soft ground to dry. 22

It is also conceivable to spray local open areas with aquatint to make a stronger contrast to the areas that have not been etched. One's imagination is the only limit. Just bear in mind that where the ink is opaque, it serves as stop-out and thus produces white areas in the print. (See also Washings as Acrylic Resists, p. 34). Stopping Out If one wants to stop out an area, it can be painted over with a coat of Acrylic Stop-Out Varnish and left in the drying cabinet for five minutes , after which the etching can be reassumed. If the areas in question are large or have bold lines in them, it is recommendable to de-oxidize the plate before stopping out (seep . 34). Removing the Etching Grounds - Cleaning Tools To remove the soft ground from the plate, use ordinary dish detergent, cold water and a kitchen sponge if no binder has been used. If the soft ground has been left on the plate for several days or was mixed with acrylic binder, the easiest way to remove it is with the usual solution of soda crystals (see p. 44). Wash off rollers, glass plates and tools in lukewarm water and, if necessary, detergent. Do not use hot water - that makes the relief ink stick. Top left: Hard ground drawing etched 40 minutes. Artwork : Poul Janus Ipsen. Opporsite: Softground washing etched 3 hours. Artwork : Henrik Broegh.

SUMMARY 1 2

3

2

3

Roll-On Soft Ground Mix 2 parts ink with 1 part binder on a glass plate. Roll the etching ground evenly onto the glass plate; first as a relatively thick layer, which is used as a reservoir, then as a thin dry layer. From this dry layer roll the etching ground onto the copper plate from all sides and in thin coats. A glimpse of copper must be visible through the translucent ground . Leave the plate with the wet ground in room temperature for 10 to 15 minutes - just enough to dry its surface a little. It will then be suitable for soft ground etchings. Draw-Through Soft Ground Soft ground drawings can be made on a sheet of soft paper which absorbs the ink. In this case you leave the plate in room temperature 5-10 minutes before starting. You can also paint directly into the soft ground with demineralised water, or you can use various drawing requisites directly in the soft ground. After 20 minutes in the drying cabinet it becomes a hard ground, which can either be worked further or etched right away.

PS. If your artwork takes a long time to do, it is advisable to use less or no binder in the ink. Without binder you have four hours to work in the soft ground before it hardens . The etching ground must be totally dry before you start etching.

2

3 4

6 7

1 2

3

Soft Ground Impressions Place the plate on a piece of paper on the etching press bed. Place the objects on top of the plate. Coat a piece of soft plastic foil evenly with salad oil and place it (oily side down) on top of the plate and the objects. Finally cover the whole thing with a piece of thin pasteboard without structure. Run the plate through the press. Remove the pasteboard first, then carefully pull off the plastic. If the foil sticks to the ink, it is because there is not enough oil on it. Finally remove the objects gently. Harden the plate for 20 minutes. The soft ground now becomes a hard ground which can either be worked further as such or etched right away.

Roll-On Hard Ground Mix 1 part binder with 2 parts ink on a glass plate. Roll the etching ground evenly onto the glass plate; fist as a relatively thick layer, which is used as a reservoir, then as a thin dry layer. From the glass plate roll the etching ground onto the copper plate from all sides and in thin coats. A glimpse of copper must be visible through the translucent ground. The etching ground can now be hardened for 20 minutes in the drying cabinet and used as a hard ground. PS. The amount of binder that is mixed into the ink determines the time required for hardening and drying.

Materials Water-basedink Graphic Chemical Water Based Ink Crimson Red No. 1661 Binder : Lascaux Transparentlack No. 2060 Stop-Out: Golden Acrylic Stop-Out Varnish Mild ·-solution of ammonia and water : Ajax Window Cleanser

23

SPRAYED AQUATINT workable ways of applying the aquatint: as lines , areas with different density , clouds , splatters , layers of gradually increasing thickness , etc . In short , the airbrush works by air pressure and functions like a spray gun .

Applying the Aquatint Run some water though the airbrush to make sure that it is clean before screwing on the jar containing the aquatint. An airbrush must always be very thoroughly cleansed , as it will otherwise easily clog up . Rinse it with clean water after use . If it does clog up , make a mild solution of soda and water and run that through . When the clogging is dissolved , run some clean water through it again before use.

General Remarks As aquatint we use an acrylic resist , diluted one to one with demineralised water before it is sprayed onto the copper plate . When dealing with acrylic grounds , it is of general importance to observe correct proportions and mix the ingredients well. The aquatint is instantly ready for use . For the application of the aquatint , we need an airbrush and a compressor. Although the product is non-toxic , it cannot be healthy to breathe in the tiny ink particles that spray from the airbrush . It is therefore recommendable to wear a dust mask and install a cooking canopy or some other form of exhaust system in the aquatint cabinet (see p. 81 ). One applies the aquatint to the plate by spraying it on with an airbrush. This tool makes for a wide range of possibilities for creating different grey tones in one etching . The dotted structure may of course be applied to the copper plate in a uniform surface as is known from traditional aquatint , but the airbrush provides many other 24

Place the copper plate almost vertically against a piece of white paper . Fill the glass container under the airbrush with the aquatint ground . The density of the aquatint grains is determined by the amount of air that is admitted into the etching ground . Adjustments are made partly by loosening or tightening the valve of the spray gun , partly by changing the distance between the gun and the plate . It may be difficult to see the grains on the copper plate , which is why it is important to place it against a white background sheet , which will show the position and quality of the aquatint grains. You achieve the finest aquatint by adjusting the airbrush to admit the highest possible amount of air in proportion to the etching ground. As in all other aspects of life , practice makes perfect ; therefore the training on paper or cardboard is very useful. I recommend starting with the exercises described in the instructions on how to use the airbrush . If you want a coarser aquatint , adjust the airbrush to admit less air, and increase the distance to the plate. This presentation distinguishes between the uniform aquatint and the modulated aquatint.

Uniform Aquatint The aim here is to spray a fine , misty surface onto the plate, not to cover it completely. Hold the brush at arm's length and spray the copper plate evenly, going beyond the edges of the plate to avoid irregularities. Use smooth , even movements in parallel lines across the plate from left to right and right to left, moving simultaneously down towards the bottom of the plate. Try the technique on a piece of white cardboard first for practice, until you are able to see the aquatint forming an even, misty dotted structure on the cardboard. Then attempt the technique on the cleaned, de-greased copper plate, but keep a piece of white paper behind the plate to show you what you are doing. If you make a mistake, simply wash off the aquatint immediately in cold water , dry the plate and try again.

When applied, dry the aquatint for 20 minutes in the drying cabinet and etch it as you would a conventional aquatint. It is possible to take the plate out of the ferric chloride at any time and rinse, inspect and stop out again . Just remember to de-oxidize the copper plates before stopping out, as the stop-out varnish will otherwise not adhere properly (see de-oxidizing , p. 44) . You can create sharp outlines within the composition by using masks and stencils made of paper or card . The outlines may then become bases for the use of other techniques - e .g . transferring a fragment from a photographic image by means of photopolymer film .

Top: Aquatint Cabinet (see also p. 81 for 0.1.Y. instructions) . Bottom-left : Hold the brush at arm 's length and spray the copper plate evenly, going beyond the edges of the plate to avoid irregularities . Bottom -right: Sprayed uniform aqua tint (Size 1: 1 I 100%) .

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I

--1 Modulated Aquatint The technique of spraying on the modulated aquatint is not that different from that of the uniform aquatint. The aim is of course different - what is wanted in this case is not an even structure, but a creative use of the airbrush which enables the artist to produce modulated areas of varying density - as in an airbrush painting.

The modulated aquatint is effective for creating spatial effects in abstract composition , for emphasising the weight of three-dimensional objects , and for many other purposes requiring modulated tones. Compared to conventional aquatint, which has very sharp edges made by the stopping-outs on the plate, this method makes it easier to achieve a gradual transition from one tone to another. As always , the most densely coated areas produce the lightest tones in the final print and vice versa. The experienced ,aquatint sprayer' thus does not need to etch, stop out, etch , stop out , etch etc. , but you can of course spray the aquatint on evenly as described above, and

26

use the stop-out in the traditional way if you feel more comfortable with that. Remember to de-oxidize before every coat of stop-out (p. 44) . Any area of the plate that has not been sprayed will naturally etch as an open bite. If you wish to avoid this , begin by spraying a thin coat onto the whole plate before commencing the actual composition. Other Options The aquatint-sprayed copper plate may form the basis of the most beautiful washings - they are the intaglio version of watercolour painting . The effect can be achieved in many different ways:

•

•

Brush and dilute the freshly sprayed and still wet aquatint ground in smaller areas or all over the plate with demineralised water . Dry it in the drying cabinet and etch it - the results are stunning! Spray a very fine aquatint onto the plate . When it is dry, place it in a photo tray and paint local areas with

Edinburgh Etch. (Stirring it into wallpaper glue will revent it from running.) This method corresponds to a spit bite in the system of conventional oil-based etching grounds. The longer the ferric chloride (see illustration page 19) remains on the plate , the darker the etched tone will become. You can avoid sharp edges completely by painting around the etched areas with water. The depth of the bite is controllable at any time : rinse in water , inspect , and brush on the ferric chloride again if necessary . Paint or dab the dry etching ground with a brush or cotton bud and a mild solution of ammonia and water or ammonia-based window polish (ammonia dissolves the hardened etching ground) . If you do not de-oxidize the plate after each etching before applying a new etching ground or stop-out, the ferric oxide generated on the surface of the plate will cause the etching ground or stop-out to loosen and break up during the following etching process (see p. 44).

Stopping Out De-oxidize the plate, paint on a thin coat of Acrylic StopOut Varnish and dry the plate in a drying cabinet for 5 minutes (see also p. 80 ff). Removing the Aquatint and Stop-Out As all other acrylic-based etching grounds, the aquatint ground is removable in a solution of soda crystals and water. If time is of the essence, put the plate in a caustic soda solution (seep . 44).

Opposite left: This aquatint has been etched and stopped out by turns like a traditional aquatint . Opposite right: This plate has had an even layer of aquatint first, then another layer on the lower right section, and finally a washing with a mild solution of ammonia and water in the wet aquatint . Top left: Aquatint sprayed on in several layers with the use of masks . Top' right: Aquatint detail sprayed and stopped out by turns.

27

SUMMARY

2

3 4

5

Mix the aquatint with 50% demineralised water in the airbrush container. Run some water though the airbrush to make sure that it is clean before screwing on the container with the aquatint. An airbrush must always be very thoroughly cleansed, as it will otherwise easily clog up. Rinse it with clean water after use. If it does clog up, make a mild solution of soda and water and run that through. Place the de-greased copper plate vertically in the aquatint cabinet against a sheet of white paper. Hold the brush at arm's length and spray the copper plate evenly, going beyond the edges of the plate to avoid irregularities. Harden the aquatint for 20 minutes in the drying cabinet before etching or stopping out. PS. It may be difficult to see the grains on the copper plate, which is why it is important to place it against a white background sheet, which will show the position and quality of the aquatint grains.

Top: Aquatint combined with soft ground washings. Opposite: Aquatint sprayed and stopped out with stop-out varnish, oil and water by turns. Artist : Bent Holstein.

Materials Spray-On Aquatint: Badger Acrylic Aquatint concentrated + Demineralised water Stop-Out: Golden Acrylic Stop-Out Varnish Wallpaper glue mixed with Edinburgh Etch Mild solution of ammonia and water : Ajax Window Cleanser

28

Lift ground painted with etching ink mixed with olive oil, then sprayed with Badger Acrylic Aquatint and etched for three minutes in the Edinburgh Etch, given a coat of Golden Acrylic Stop-Out and worked as a hard ground . Etched for another twelve minutes . Worked in with a dry point needle after the removal of the etching grounds. Finally, as collograph medium, Artes Libera/es poster colour was applied. Artwork : Terje Resell

... LIFT GROUNDS General Remarks This chapter presents two very different lift ground techniques . The first method builds on the fact that oil repels water . It corresponds to the conventional sugar lift techniques . The second method requires that the studio is equipped with an exposure unit for photopolymer film. The latter is faster and for some artworks more exact.

Lift Ground Using Oil and Water The fact that oil repels water gives us many sources for fat or oilbased lift ground media . You can use butter, lipstick, Vaseline , wax crayons, etc. In the Printmakers ' Experimentarium , however, we have developed our own lift ground , which serves for all types of subjects : mix a tiny bit of etching ink with olive oil to the desired consistency. You can paint it on with a brush or write with it by means of a pen directly on the de-greased copper plate . It is important to use olive oil , as this product enables the lift ground to congeal if you put it in the refrigerator for a few minutes.This prevents it from running later in the working process. To the plate with the lift ground you must now apply a hard ground . For that purpose you mix an acrylic binder with demineralised water and add a colour pigment so that you can see what you are doing . Once the plate has hardened and the ground been lifted, you can work the surface as a hard ground with various drawing tools. Put the plate with the lift media in the refrigerator to congeal. After a few minutes , remove the plate with the congealed lift ground from the refrigerator and place it horizontally in the aquatint cabinet. Spray on a thin coat of hard ground from all four sides. Then harden the hard ground in the drying cabinet for approximately 20 minutes. Now lift the painted areas under the hard ground in lukewarm water using a brush. Remove the etching ink in the lifted areas first by means of salad oil on a soft piece of cloth. Finally de-grease the plate with scouring cream or magnesium carbonate and de-greaser. Rinse it

as usual and dab off in a newspaper before drying it for a few minutes in the drying cabinet. When the plate is dry, spray it with an even coat of aquatint and harden it for 20 minutes before etching and stopping out as during the usual etching process . Removing the Etching Ground When the etching is complete, remove the aquatint ground and the hard ground in soda crystals and water (p. 44) . The plate is now ready for further processing with other media , or for wiping and printing. SUMMARY Mix some etching ink with olive oil to the desired consistency. 2 Paint it on with a brush or write with it with a pen directly on the copper plate. 3 If the medium is fluid, let it congeal in the refrigerator for a few minutes. 4 Place the plate horizontally in the aquatint cabinet and spray it from all sides with a spray-on hard ground.• 5 The plate must be hardened for approx. 20 minutes in the drying cabinet. 6 Place the plate in a tray with lukewarm water and lift the hard ground using a brush. 7 Remove the etching ink in the lifted areas by means of salad oil. 8 De-grease the plate with scouring cream and CPS degreaser . 9 Rinse in running water, dab the plate in a newspaper and dry it. 10 Spray on hardground and harden it for 20 minutes before etching the plate. Spray-on hard ground for lift ground Mix 1 part Lascaux Transparentlack No. 2060with 2 parts of demineralised water and add colour pigment. Materials Lift medium: Etching ink+ olive oil Spray-on hard ground: as above same as the binder for soft ground Colour pigment .,Kremers Farbteig Heliogen " or other Scouring cream CPS de-greaser

31

Reversed Lift Ground Several lift ground media can also be used reversedly ; directly on the plate . If, for instance , one uses a wax crayon or a lipstick to draw directly on the plate without applying the liquid hardground as for the lift ground , one can move straight to the application of the aquatint and the subsequent etching , after which the plate must be stripped , rinsed and de-greased with a bit scouring cream , water and a sponge (see p. 44) . After this , the plate is ready to be wiped and printed . Lift Ground Using Photopolymer Film Laminate a de-greased copper plate as explained on page 50. Paint with some kind of lightproof medium on the top layer of the photopolymer film or on a piece of drawing foil in the areas you want to lift. ,,Schminke Abdeckrot " is completely lightproof and perfect for the purpose.

You can also cut or tear out stencils or masks from aluminium foil and place them on top of the photopolymer film . Now expose the plate under ultraviolet light for 5 minutes with the lift medium on top . Remove the lift media

32

and the top foil. Develop the plate for five minutes to be sure that the film is opened to the copper as described on page 51. Dry the plate and spray a fine layer of aquatint over the entire plate. Let the aquatint harden for 20 minutes and etch with the photopolymer film as etching resist to the desired grey tone. It is of course also possible to laminate the photopolymer film on an already etched plate , lift certain areas , apply aquatint and etch the lifted areas . In this case it is extremely important to de-oxidize and de-grease the plate thoroughly before applying the film.

Removing the Photopolymer Film and Aquatint When the etching is complete , remove the aquatint ground and photopolymer film in soda crystals and water (p. 44) . The plate is now ready for further processing with other media , or for inking up and printing .

..

...

aterials Drawing foil or lightproof masks Schminke Abdeckrot or other medium Photopolymer Film Badger Acrylic Aquatint

Lift ground using photopolymer film and aquatint. Artist: Nils Erik Gjerdevik

WASHINGS AS ACRYLIC RESISTS General Remarks This chapter presents two different washing media (techniques) for making direct washes on the copper plate. The first method is fast and makes use of the previously mentioned soft ground techniques and media developed together with the acrylic resist etching system. The second, known under the name ,,White Ground" , was invented back in the 1960s by Frank Cassara . It is quite an interesting slow working method that fits perfectly into the realm of non-toxic intaglio techniques presented is this book. Soft Ground Washings The water-based ink, which we used for rolled-on soft and hard grounds , also comes in a black version . It is coarser and contains more pigment. If you paint it directly onto a glass plate with demineralised water, the pigment grains are clearly visible floating around in the water.

34

Applying the Wash Media The ink may be transferred directly to the de-greased plate by means of a brush or an ink roller or mixed with about six parts water in a bowl and painted on . While the plate dries (use an electric hair dryer), the water evaporates and the pigment remains. When the washing has dried completely , one can stop out selected areas . It is interesting to note that the ground will slowly break down after two to three hours of etching . This happens because it does not contain an acrylic binder . Acrylic studio paints which are this rich in pigment may also be ideal for washings.

If the process described above is carried out on a copper plate which is subsequently placed in the drying cabinet, the pigment will remain on the plate. Etchings of short duration produce a ,,spit bite"-like effect. During long etchings, the pigment will gradually dissolve.This happens very slowly, and it is therefore possible to control the process . The depth of the bite depends on the amount of

~ washing with different media diluted with demineralised water. At the top, the plate had heavy applications , and at the bottom very diluted applications of the different media. Left: Graphic Chem. Black No 1659. Center: Hunt Speedba/1 Screenfiller. Right: Badger Acrylic Aquatint .

SUMMARY

water added to the acrylic. The thinnest coat makes the deepest etching and vice versa. The result is an etching which , in the final print, will present a multitude of tones, but without the dotted structure of the aquatint. This etching resist works perfectly on the entire plate when rolled on and painted with demineralised water or brushed onto lifted areas of the plate (see lift grounds pp. 31ft).

2 3

4

The ink has to be completely dry before etching . When it has been etched, do not rinse under running water - the water might lift the soft ground off the plate since it contains no binder. For inspection during the etching, put the plate in a tray with water and move it gently just enough to remove the remains of ferric chloride and allow you to evaluate if it needs more etching . Removing the Wash Media The ink can be removed in lukewarm water with a sponge. If it has got hard to get rid of, dissolve it in soda crystals and water (seep. 44) .

Paint the ink directly onto a glass plate with demineralised water, or mix it with 6 parts demineralised water in a bowl. The diluted ink may be transferred directly to the degreased plate by means of a brush or a cotton bud. The ink can be rolled on like a roll-on hard ground, and washes can be done directly with a brush in the wet rolled-on ink. Before etching, the etching ground must be hardened in the drying cabinet until it is completely dry. The drying time depends on the thickness of the etching ground.

Material Graphic Chemical Water Based Ink, Black No. 1659 + demineralised water Alterhative : Hunt Speedba/1 Screen Filler

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White Ground details. Textures have been applied to both plates . Left: The cross has been built up with more layers of white ground. Right: The cross has been painted with water directly in the thin white ground.

White Ground General Remarks White ground is a mixture of white pigment , soap flakes and linseed oil. After mixing the white ground it is painted directly onto the de-greased plate . It is a semi-permeable ground that breaks down during etching where it is applied as a thin layer and totally resists biting when applied thickly . Therefore , a range of tones from white through greys to black is possible . Preparing the White Ground Use a large mortar and a pestle . Mix 1 cup of dry titanium white powder with 2 cups of blended soap flakes (or powder) in the mortar. Make a mound of the mixture with a little depression in the centre and slowly add 112 cup of raw linseed oil while you are mixing with the pestle until you have a thick , consistent paste . Do it thouroughly as this is the most important part of getting a well-working ground . Now slowly add 1 cup of demineralised water while you are stirring the mixture until it has the consistency of whipped cream .

36

You can keep the white ground in a sealed plastic or glass jar for up to two months. In the meantime the mixture will gradually loose moisture and the oil will separate a little. In this case you just have to add a little demineralised water and stir well to get back to the original state . Throw the paste in the toilet after two months . Applying the White Ground Place a de-greased and backed copper plate on a piece of paper bigger than the plate. Take an appropriate amount of white ground from the jar with a pallet knife and thin and mix it with a few drops of demineralised water on a glass plate. The amount of water depends on the method you are using:

•

Applied in the consistency of tempera paint with a sponge brush so that it appears milky white on the plate . This can be worked into with a clean watery brush , wooden sticks , textures etc . to make areas

darker, or worked over with more white ground to prevent biting. •

•

When slightly diluted with water, the white ground can be dabbed onto the plate with a sponge or soft cotton cloth wrapped around cotton wool to produce greys which can be removed for blacks or added for whites. Drawn with soft brushes directly with diluted white ground, building up for whites and removing for blacks etc.

With the help of a hair dryer you will be able to cause the water to evaporate. Try not to overheat the ground - if you do so, the oil will harden and the ground will turn yellow the result is that you will have trouble manipulating the ground any further. When the water has evaporated, the ground is white and you can apply another thin coat on certain areas. When the water has evaporated from these areas, they turn grey. If you etched the plate now and printed it, you would end up with a medium grey tone. To create lighter tones or white areas, you must add more white ground. Adding more coats corresponds to stopping out areas where the ground looks opaque. To get an idea of the final print before you etch it, you simply place the plate in indirect light. When you are satisfied, just let the white ground air dry over night. When the etching ground has dried completely, spray it with an even coat of aquatint (see pp . 25ft). Let the aquatint harden for 20 minutes in the drying cabinet and etch the plate in a tray with pure ferric chloride (normal 45-47 Beaume degrees). Gently put the plate in the ferric with the image side up - do not agitate the tray. Let it etch for 30-80 minutes. Remove the white ground, de-oxidize and rinse with water. While the plate is under running water, gently polish the image area of the plate with chalk powder to bring up the whites and subtle greys. Do it carefully so you do not remove the delicate aquatint. Rinse, dry and print the plate.

Bits of white ground will be left in the ferric chloride after etching . Either keep this ferric in a special container for white ground etchings or pour it through an old stocking or plastic strainer . Applying White Ground to an Etched Plate Clean, de-oxidize and de-grease the etched plate thoroughly and back the plate with packing tape . Brush Stop Out Varnish onto those areas that are to remain unbitten and harden it for 5 minutes in the drying cabinet , or apply a lift ground to the areas you want to etch . Finally apply the white ground and etch it as described above . Removing the White Ground The white ground can be removed in lukewarm water with a sponge. Use soda and water solution if acrylics have been used (seep. 44) .

~UMMARY

2

3

4 5 6

Take an appropriate amount of white ground and thin and mix it with a few drops of demineralised water on a glass plate. The white ground can be applied to the plate by using sponge brushes, soft brushes or dabbed with a cotton ball. It can be worked into with a clean watery brush, wooden sticks, textures etc. to make areas darker, or worked over with more white ground to prevent biting. Before etching the white ground, it must be air dried over night. The drying time depends on the thickness of the etching ground. When completely dry, spray on an even layer of aquatint and let it harden 20 minutes in the drying cabinet. Etch the plate (face up) horisontally in a tray in pure ferric chloride . Remove the etchings grounds, ink up and print.

M:1te1i, I 1 cup powdered titanium white 2 cups Ivory Snow powdered detergent Alternative : Soap flakes blended to powder. Y2cup raw linseed oil 1 cup demineralised water

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COLLOGRAPH TECHNIQUES

Detail from already etched plate r eworked with collograph paint . Artwork : Gunnar Nielsen .

With some studio paints, which are very rich in pigment, it is possible to paint directly on the plate (even on a plate that has already been etched) and then dry the acrylic paint in the drying cabinet. As it dries, the acrylic will harden on the plate and become incredibly durable. The plate is now ready for wiping and printing . Where the coat of paint is thick , the print will be light; where it is thin , the print will be dark . The painted areas of the plate will produce a relief print in the paper. This makes it possible to obtain many interesting effects by combining the techniques of intaglio and relief printing (wiping and rolling, respectively) in the application of etching inks. By painting with a thin solution (mix with demineralised water) you are able to ,,close" an aquatint that prints to black, and if you mix the paint with carborundum powder, you may create an aquatint-like effect. The paint can be removed in a strong solution of soda crystals and water (see page 44) .

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Materials Artes Libera/es Colour-Kit (Alternative : Hunt Speedba/1Sere e n Filler'}

ETCHING BACKING AND STRIPPING

ETCHING

Ultimately, those answers reflect a serious ignorance, partly of the consequences to health and environment that the use of such acids can have (see page 9), partly of the alternatives. Although many printmaking studios have stopped etching in acid, several of them are still cutting themselves off from the benefits of using ferric chloride, as they treat it incorrectly: They have been informed that ferric chloride does not generate toxic fumes and therefore does not require an exhaust. This is true enough, provided that it is handled appropriately. It is strongly recommendable to buy ferric chloride in liquid form, directly from the chemical factories. Unfortunately, printmakers quite often buy ferric chloride crystals from the artists' supply shop and dissolve those in water themselves, without the least consideration for the violent generation of extremely dangerous fumes (chlorine) that takes place when ferric chloride and water are first brought into contact. Dissolving the crystals in water on one's own is, quite simply, very dangerous to one's health.

General Remarks Since the days of Rembrandt, printmakers have been using nitric acid and ,Dutch mordants' to etch in copper. At the beginning of this century, ferric chloride was introduced into gravure, primarily for technical reasons. Not until the advent of stricter environment protection rules in the electronic industry in the 1980s was nitric acid replaced completely by ferric chloride, e.g. for etching circuit boards. Ferric chloride is a salt. If treated correctly, it is, as opposed to nitric acid, quite safe for health and environment.

Despite the fact that new and very effective methods for ferric chloride etching have been developed in the industry, I have noted that many printmakers and schools continue to use nitric acid, muriatic or hydrochloric acid, Dutch mordants, etc. When asked why, they typically answer in phrases like: ,,Ferric chloride works too slowly; it forms a sediment which makes it impossible to follow the process; you have to etch the plates face-down to avoid the crystallisation which would stop the etching process; our exhaust system is very efficient etc., etc."

40

If the process is absolutely necessary, it should take place outdoors, and safety goggles, an acid gas mask and long rubber gloves are required safety precautions. For etching purposes the best results will be achieved by mixing one kilogram of ferric chloride crystals with 2.5 litres of water. As mentioned, the method is not recommendable, and one is often left with a turbid, rustylooking liquid, which certainly does not look like a trustworthy alternative to nitric acid in the etching process.

Etching in tank: Use a clip to fasten the packing tape ,,plate hanger" to the rail as shown on the photo. A larger number of smaller plates can naturally be etched in one go.

Etching Copper in Ferric Chloride The plate can be etched vertically in pure 72% Ferric Chloride in a tank or horizontally in an open tray in ferric chloride plus a mixture of water and citric acid powder (the so-called Edinburgh Etch). Liquid ferric chloride is cheap and will last through years of daily use. It can be purchased directly from chemical factories . Etching in Tanks When etching in tanks , use pure ferric chloride (72% = 45-47° Beaume) in liquid form . Use a clip to fasten the packing tape ,,plate hanger'' to the rail as shown on the photo. A larger number of smaller plates can naturally be etched in one go, and this is of course an advantage in larger studios and schools, where several people wish to use the facility at the same time. The slip of the ,,hanger" fixed to the plates can serve as a nametag showing whom the plate belongs to, and it can also be used to write down the exact time when the etching was commenced. A significant advantage of tank etching is that the open surface is so small that practically no evaporation takes place . However, it is naturally

advisable to put on the lid when the tank is not in use, in which case it is also unnecessary to pour the ferric chloride back into the bottle (until it is ,worn out'). A full tank (like the one on page 84) that contains about 35 litres will last approximately four years of frequent, daily use. If the ferric chloride is out of use for a period of time , it may lose its edge. You can ,whet its appetite ' by feeding it a piece of copper a few hours before etching . When the ferric chloride is worn out , it must be turned over to the proper authorities for destruction . The safest and easiest way to empty the tank is by means of an aquarium pump. Etching in Open Trays For open tray etching I recommend the Edinburgh Etch. This etching technique was invented by Friedhard Kiekeben in Edinburgh - hence the name. Apart from ferric chloride it contains citric acid powder. The Edinburgh Etch performs the etching considerably faster than pure ferric chloride in trays . That is due to the 41

addition of citric acid, which also has another important function : the crystal residue which arises in the pure ferric chloride during the etching process (and constantly has to be swept away with a feather) is not formed in the Edinburgh Etch at all - the molecules are practically devoured by the citric acid before they have time to crystallise . This means that no feather is needed , the plate must be placed with the etching ground facing upwards, and the whole etching process can be observed through the clear amber liquid. The ingredients for the Edinburgh Etch are: 4 litres Ferric Chloride solution 72% (45-47 Beaume degrees) 250 ml citric acid powder (frequently used in marmalade) 750 ml water The quantity of the etching solution should be adjusted to the needs and the capacity of the studio in question , but the proportions of the ingredients must always be the same as described in the recipe. That is, if the quantity of one component is reduced to 50%, the other components must follow. Do not dissolve citric acid powder in ferric chloride or cold water - it is difficult , and besides that you risk spattering ferric chloride onto yourself . Dissolve the citric acid powder in a bit of hot water while stirring , and then fill up with cold water and ferric chloride to produce the required quantity. When in contact with copper , ferric chloride reacts with predatorial hunger - more wants more. It might therefore be useful to ,feed' the solution with a few scraps of copper before the actual plate is etched. As mentioned above , that whets its appetite and reduces the etching time required. To ensure a controllable bite, a freshly made Edinburgh Etch must always be ,kick-started ' before the first etching . That is done either by mixing a little bit of used Edinburgh Etch into the fresh solution , or by putting a small piece of copper into the container . This can be done the day before . 42

Etching i tray. Make a ,,plate hanger" which reaches up above the edge of the tray.

Disposal When the solution is worn out, pour it into ajar and turn it over to the appropriate authorities. Remember to label the jar, describing what it contains and mentioning that the solution has been used for copper etching . Safety No exhaust system is needed - only normal ventilation . Use rubber gloves and safety goggles against spattering . In case of skin contact , rinse immediately with lots of water. Clean your hands thoroughly before eating , drinking or smoking .

.. Etching Zinc with the Bordeaux Etch The safest way to etch zinc as regards health and environment is to use the so-called ,,Bordeaux Etch''. That means etching in a concentrated solution of copper sulphate in an open tray. It is a cheap, easy and effective way of etching zinc. Copper sulphate (CuS04) is a salt and not an acid. When etching zinc in a copper sulphate solution there is no production of harmful vapours, but a very modest amount of hydrogen gas is produced. This hydrogen is absolutely safe and must be allowed to escape out into the room. Therefore never put the lid on the tray while etching. The method was developed by Cedric Green, and the name refers to a fungicide (Bordeaux Mixture or Bouillie Bordelaise) used by Bordeaux winegrowers against mildew.

of the tray. That will be very useful when the plate is lowered into or pulled up out of the liquid. Lower the plate into the bath and the bare zinc will turn black immediately. This black sediment is finely dispersed copper. Prevent copper build-up by feathering the plate regularly. This ensures a continuous stream of fresh solution in lines and open areas. Settling of sediment on the top of these areas will retard the biting of the plate, and you may get a copper build-up, which can be hard to get rid of without scratching the etching ground. In that case it is a good idea to move the plate to a fresh solution for a moment to remove the sediment and then continue in the ,,old" solution, remembering to feather regularly. As the solution weakens, the colour of the newly formed sediment changes from black to reddish brown. After etching, take the plate out of the bath and rinse in running water.

The ingredients for the Bordeaux Etch are:

The stronger the solution, the faster it etches. When starting with a fresh mixture, the colour of the solution will be a transparent light blue. During use it will become more and more colourless and etch more slowly. After use cover the etching tray with a lid or pour the mixture back into an acid-proof plastic container. When pouring it back through a funnel into the can, you can filter off the sediment deposited during the etching process.

Disposal When the solution is worn out, pour it into a jar and leave it for a couple of days until the copper and zinc hydroxide have deposited as a sludge. Pour off the clear liquid and neutralise it with sodium carbonate (washing soda) until the pH value goes up to between 7.0 and 8.0 (test with a strip of indicator paper) then it can go down in the drain. The remaining zinc hydroxide/copper sludge has to be turned over to the appropriate authorities. Remember to label the jar; describing what it contains and that it was used for zinc etching.

Pour some lukewarm water into a mixing bowl. Carefully take copper sulphate from its container with a plastic spoon. Add the sulphate to the water and stir carefully for a few minutes without spattering it about until all of the copper sulphate has dissolved. Pour the beautiful blue solution into an etching tray, and it is ready for use. There must be 2 - 3 cm of the liquid over the bottom of the tray. Use rubber gloves and protection goggles while mixing the solution.

Safety No exhaust system is needed - only normal ventilation. Use rubber gloves and safety goggles against spattering. Wear a dust mask when handling the copper sulphate powder. In case of skin contact, rinse immediately with lots of water. Clean your hands thoroughly before eating, drinking or smoking.

Etching the Zinc Plate Back the plate as described on page 44 before etching. Make a ,,plate hanger"which reaches up above the edge

www.greenart.info/galvetch/

50-100 grams of copper sulphate to 1 litre of water

PS. For more information see Cedric Green's web-site:

43

BEFORE, DURING AND AFTER ETCHING Backing the Plate Before etching , back the plate either with packing tape or Filmolux stop-out foil. Use a piece of packing tape to make a ,,plate hanger "which reaches up above the edge of the tank or tray. That will be very useful when the plate is lowered into or pulled up out of the liquid.

If the backing tape is hard to remove from the plate before printing , soak it in hot water or heat up the plate in the drying cabinet , and the tape will come off easily. Not all packing tape is equally suitable for backing , as some types are rather hard to get off. The best one for the purpose is from Cartongraf(Italy), and it is sold worldwide . De-Oxidizing Whenever copper has been in contact with ferric chloride it starts oxidizing. Before applying any new etching ground or stop-out , the oxidation must be removed - if not, the etching ground will fall off under continued etching. This can be done easily in a tray with a mixture of vinegar and salt. Simply place the plate in the solution and it deoxidizes immediately . Rinse under running water, dry the plate in the drying cabinet and apply stop-out or an etching ground. The de-oxidizing solution is made by mixing 4 tablespoons of fine salt with 1 litre of vinegar (stir thoroughly) . The solution can be kept in a bottle until it is worn out.

The plate is backed with packing tape and supplied with a ,,plate hanger ".

2 3

Removing the Etching Grounds - Stripping Acrylic- and water-based etching grounds as well as photopolymer film can be removed in a mild solution of washing soda and water. All remains from the stripping of the plates , are to be disposed according to the environmental regulations in your area. Soda crystals are best dissolved in hot water . Washing soda is an alkaline product which may irritate the skin . It is therefore preferable to use rubber gloves while stripping the etching grounds .

44

4 5 6

Stir 6-1O tablespoons of soda crystals into 2 lites of hot water. When the soda has dissolved completely, pour the solution into a photo tray. Place the plate in the tray with the etching ground facing up. After 5-20 minutes the ground can be washed off under running water. Finally remove the packing tape on the back and dry the plate. The stripper can be used for several plates before it is finished .

PS. If an etching ground has been applied very thickly, it might require a stronger solution or a longer time in the stripper . If you are in a hurry, you can use caustic soda (only for copper) .

....

l* ~

PHOTOPOLYMER FILM AND SOLAR PLATES

PHOTOPOLYMER FILM AND SOLAR PLATES

General Remarks We use photopolymer film or Solar plates (photopolymer plates) to transfer drawings, photocopies, photographs and computer generated stencils for intaglio prints. Photopolymer is a relatively new medium in intaglio. Seen from an artistic perspective, especially two forms of photopolymer are interesting:The Photopolymer Plate (in some places also called ,,Solar Plates") and the Photopolymer Film. The plate is used in letterpress printing, especially in flexography, where the toughness of the polymer enables huge print runs to be made millions of copies at a time. It comes in different thicknesses. The photopolymer film is available in different thicknesses as well; it comes in rolls and is used in the electronic industry for the production of circuit boards. The film is about seven times cheaper than the plates. The principle behind photopolymer film is different from that of metal-base photopolymer plates. In photopolymer film, the printing surface consists of a thin transfer

46

emulsion. Tonalities are reproduced according to the size of the dots that make up the image, just as in offset or photo-etching. Photopolymer film has a rather narrow tonal range, which limits its usefulness in producing continuous tone images. However, the emulsion is harder than on polymer plates, so highlights are easier to produce with this material. Hairlines also reproduce extremely well on photopolymer film. The advantage of the photopolymer plates lies in the fact that they produce extremely fine grey tones from continuous tone positives and stochastic halftone positives and that they can be used for almost endless print runs because of their strength. Their exquisite rendering of greys also makes them the preferred choice of many photographers for photo gravures. This also constitutes the limitation of the photopolymer plate compared to the photopolymer film. The film, which can be laminated onto a great number of materials, offers a wider range of possible applications

r than do the plates, one of the reasons being that it enables drawings, washings and photographs to be etched directly into a copper plate and then subjected to further processing with all the other acrylic-based intaglio techniques. Photopolymer film and photopolymer plates are sensitive to most sources of UV light (usually of 320 - 450 nano, metres). According to the manufacturers, the technically best result is achieved with a light sources of 365 nm ; (corresponding to the Mercury Vapour Lamp mentioned ton page 82). In practice, it is hard to tell the difference. ..Mercury vapour lamps are cheap and they work just as well as the professional exposure units previously used ··for offset plates in the printing houses. What Is Photopolymer? ,Poly' means many, and ,-mer' means molecule, i.e. a 'link in a chain. The polymer, a chain with many links, is Icreated when a number of molecules (-mers) are chained together. A photopolymer is a material that consists of a ,large number of unbound particles. When affected by ultraviolet light, the particles link together into chains, ''forming larger ,polymers'. This clustering takes place wherever the polymer is exposed to ultraviolet light and continues until there are no unbound molecules left in the area. The polymer chains, which are hardened by ultraviolet light, are incredibly strong. Unexposed molecules will not connect with the chains and are washed away when the polymer plate or the film is developed. In this way, the ink pockets and lands that are so characteristic of intaglio are created. Photopolymer Film Photopolymer film can be laminated directly onto any plate of metal, wood, perspex, etc. After the exposure of the positive, the developed or etched plate can be used in combination with other types of acrylic-based intaglio techniques (hard ground, soft ground, aquatint, etc.) On the other hand, the film can also be applied on top of a lift ground or and already etched plate so that for instance a fragment of a photograph can be etched into the already etched plate or a lifted area - the imagination is the only limit to the possibilities.

A photopolymer film surface will last for about 50 prints, and a new plate can be prepared in less than 10 minutes, provided that you have made a note of the exposure time for the original plate. The plates can be used again: soak the laminated plate in the soda solution overnight, and the film rinses right off the next morning. If in a hurry, simply prepare a stronger soda solution (see p.44) and the photopolymer film comes off after 10-20 minutes with a little help from a plastic sponge. Copper is an ideal plate material here, because the film is easier to strip off of copper than off other metals. You can cut the laminated and hardened copper plate in the plate cutter without crackling the film - just dip the plate in water before cutting. Once you have gained a bit of experience with the material, you are never in doubt as to when the plate is at the optimum stage of development. Two Techniques Generally speaking, photopolymer film can be used in two ways:

•

For a non-etching technique, which corresponds to conventional photopolymer gravure with photopolymer plates. The depth emerges in the film during the development process.

•

For an etching technique, in which the film serves as an acid-proof membrane while the plate onto which it has been laminated (copper, steel, or zinc) is being etched. The photopolymer film is extremely acid-proof and well suited for even the deepest bites.

There are several brands and manufacturers of photopolymer film on the market. For non-etchings, where you develop the image on top of the plate, the film should have a thickness of 50 microns, so that it is able to hold enough ink to print the dark areas of the image jet black. For etchings, I recommend a thickness of 15 microns, as in this connection the film only has to serve as etching ground and will be removed before the printing.

47

PHOTOPOLYMER FILM - FOR NON-ETCHINGS 1

2 3 4 5 6 7 8

Prepare and de-greasethe copper plate (p. 13). Laminate photopolymerfilm onto the plate. Expose the aquatint screen (only if the artwork is a continuous tone positive). Expose the positive. Develop the photopolymerfilm. Harden the photopolymerfilm. Ink up the plate and print it. Strip (remove) the photopolymerfilm.

The Working Process in Outline - Non-Etchings.

The Positives on Transparent Film For the positive to be exposable on the photopolymer film , it must be fixed to a transparent material , e.g. inkjet film , overhead film , drawing foil or the like. The first time you work with photopolymer film, you must calibrate the positive to match your equipment. This means that you must establish an average exposure duration, which matches your individual UV light source. You only have to do this once for each of the various types of stencils (positives) that you count on working with. The exposure duration partly depends on your technical equipment (the strength of the UV lamp, the distance to the vacuum frame , etc.), partly on the character of the artwork.

The positives that are easiest to transfer are the line drawing and halftone positives - i.e. the purely blackand-white films . Continuous tone positives, i.e. positives without a dotted screen structure , contain grey tones or large black areas and therefore require the exposure of an aquatint screen first. As the working processes are intimately connected with the various types of stencils, this presentation will deal with them separately.

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Q,(fi ·~·~ Vrln1

1. The Line Drawing Line drawings can be sketches , hatchings , letters and the like on .1,· 't' ~~' t~ transparant material , e .g . · photographic film , overhead film , ,.°?,.\ 1. • 1'1-J \.iJl ~ drawing foil , etc . The common -~ ~ .lf ': ~ denominator of these types of j ) ~-~, 1 \ artwork is that they consist in lines ~~. I t:. only, ~nd seen on a light table they . · ,· ) · \ . , contain only black or transparent ,_, 1·\/j areas - no grey tones . Hatchings /) :-~ ,f (}'\~J' may appear as a range of grey tones 1 _( . l, ( -{' because of the varying distance ~ tw±. m between individual lines , but lines they are nonetheless.

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2. The Halftone A halftone can be a photograph , a painting or any image from a computer screen . It is transferred to transparent film with the help of a stochastic screen . This means that the image is translated into a structure of different-sized dots , which in certain areas of the image are closer together than in other areas - the naked eye will perceive

..............-

this as grey tones when the image is placed on a light table . Butif you use a magnifying glass it becomes clear that the image ~ consists of dots - black or ;:-' transparent - so no grey tones . A ~ thalftone can be printed out from a photosetter at a prepress company, or it can be printed out from a regular computer and an . ink jet printer . It must always be printed out so that the dots in the blackest areas of the image covers exactly 70 per cent. (See ,,Digitally Generated Stencils " pp. 68ft).

to white . When placed on a light table , the artwork clearly shows grey tones. The thinner the application of the media, or the more diluted , the lighter the tones.

3. The Continuous Tone The continuous tone positive could be an Indian ink washing or a gouache on drawing foil, a continuous tone photograph on positive film , or a photograph printed out from a computer . The film does not contain any dotted screen structures , but only grey tones ranging from black

49

1. The corner of the film is cu 2. Inside peel-back layer is pulledof. 3.The plateis placedon top o the sprayedphotpolymer film.

Laminating the Plate . As previously mentioned, photopolymer film can be laminated onto a vast range of materials (copper, zinc, steel, Perspex, offset plates, plywood sheets, etc.). The various plate types have each their artistic effect and each present their own advantages and disadvantages (see p. 73). For the purposes of this description, we presuppose the use of a prepared and de-greased copper plate.

The film consists of three parts : The actual film, a soft inside protection foil or Mylar film, and a harder, crystalclear outside foil. The film is sandwiched between the two layers of protective foil (the coversheets). Lamination Solution Before the film is laminated to the plate is has to be sprayed with a solution of propyl alcohol and water : The lamination solution is made by mixing 1 part 35% propyl alcohol I propanol with 3 parts water. Store the solution in an atomizer.

50

Cut out a piece of film a little larger than the plate. Make a cut across one corner with a sharp hobby knife (Y2cm from the corner) . 3 Tear off the corner. 4 Pull off the soft inside peel-back layer. 5 Place the film on a newspaper with the unprotected side facing up. 6 Spray the film with a lamination solution from an atomizer (See text box at the left bottom). 7 Place the film on a Perspex plate on the etching press bed (sprayed side up). 8 Carefully lower the de-greased copper plate onto the film . 9 Cover the wet edges with plastic. 10 Run the plate through the press. 11 Remove the plastic foil and cut off excess film with a sharp hobby knife. 12 Store the laminated plate in lightproof wrapping until you need it. 2

4. The edges are covered with plastic (inside layer). 5. The plate is runned through the etching press and the plastic is removed. 6. Excess film is cut of.

Preparing the Developer Before exposing the positive onto the plate, you need to prepare the developer. The developer consists of 1Og sodium carbonate (washing soda or soda ash) dissolved in 1 litre of water. The developer works best at ordinary room temperature.

It is practical to make a large quantity while you are at it. If stored in a container with a tight lid, it will keep for an almost unlimited amount of time . I always make 20 litres at a time myself, which I then keep in a plastic container with a tap at the bottom (seep. 84). For 20 litres of water, you need 200 g washing soda. The easiest way to dissolve the little crystals is to whisk them out in a bit of hot water. When they have dissolved , fill up with the rest of the water at 20°c. But remember: it is very important to be exact: 1Og washing soda per 1 litre of water. The developing process then takes place in a photo tray. There is no reason to pour any more developer into the tray than necessary: The developer just has to cover the plate.

Safety A solution based on sodium carbonate may irritate your skin, so use rubber gloves. The sodium carbonate solution may be poured directly down the drain when you are through using it. If there are any impurities in the liquid , strain them off so as not to clog up the drain. These strained-off bits, as well as the remains from the stripping of the plate, are to be disposed of according to the environmental regulations in your area.

Spraying the film with the lamination solution

51

Calibrating Positives to the Exposure Unit In the following I will guide you through the working processes for the three main groups of positives. Following these descriptions will enable you to calibrate your exposure equipment for all of these types of procedures once and for all. Our point of departure is a copper plate, laminated with photopolymer film . 1. Calibration of the Line Drawing

2

3

4 5

6

7 8

9

Place the laminated copper plate on the vacuum frame. Leave the top protection. foil on. Place the line drawing on top with the artwork facing against the plate. Turn on the vacuum. and expose the plate in the UV light for 2-3 minutes. (Since the line drawing only contains black and white, the exposure time is not critical.) Take out the plate and remove the top foil by rubbing your hand across the edge of the plate. Place the exposed plate in the developer under normal electric light. Use a sponge in the developer as though you were washing the plate. The purpose of this procedure is to open up the unexposed areas of the copper plate, where the lines were blocking out the light Around the lines, where the plate has been exposed to the light, the surface has hardened and cannot be developed. After a couple of minutes with steady movement, the image will appear clearly. · Take the plate out of the developer, rinse it in running water and check the depth with the back of your hand. If it does not feel deep enough, develop it further. The image must appear clearly coppery in the photopolymer film. When dealing with drawings without grey tones, there is no need to be afraid of dev€loping the plate too deeply. Now rinse the plate, spray it with white vinegar from an atomizer and gently rub the vinegar into the plate. Give the plate a final rinse in cold water, and dab it in a newspaper and let it dry in the drying cabinet for about 5 minutes . Ink up the plate and print it.

appears grey, the plate will have been underexposed o overdeveloped. Make a note of the correct exposure time and use it for future exposures of line drawings . 2 . Calibration of the Halftone When we talk about a halftone , what we mean is that the image has been turned into a dotted structure with a maximum coverage of 70% in the jet black areas (see Digitally Generated Stencils pp. 68ft). If the image had been a continuous tone beforehand , the positive would have to be treated the same way as a washing and exposed with an aquatint screen first. You need to decide whether or not you wish to incorporate halftone dots in the image before printing it out. The exposure time in the ultraviolet light must also be determined by a calibration test once and for all.

2 3

4

5

6

7 8 9

If the drawing is rendered clear-cut and black , the plate will have been exposed perfectly. If the black drawing

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Place the laminated copper plate on the vacuum frame. Leave the top protection foil on. Place the halftone lith film on top. Switch on the vacuum, place a lightproof plate or' foil on top and turn on the UV light. After 30 seconds' exposure, move the lightproof plate or foil a little every 15 seconds and thus produce a photopolymer film with an exposure scale going from 30 to 120 sec. Take out the plate and remove the top foil by rubbing your hand across the edge of the plate. Place the exposed plate in the developer. Use a sponge in the developer as though you were washing the plate. Develop the plate two to three minutes with steady movement all over the plate. Take the plate out of the developer, rinse it in running water and check the halftone dots with the back of your hand. They should be felt like fine sandpaper in the coppery {black) areas of the image. If the development is inadequate, develop the plate further until you can see and feel th!3 dots clearly. Rinse the plate and spray it with white vinegar from an atomizer and gently rub the vinegar into the plate. Give ttie plate a final rinse in cold water, dab it in a new.spaper and let it dry in the drying cabinet. Ink up the plate and print it.

The print will show the image in a scale of grey tones . The area in which the tones of the image are rendered

3a. Calibration of the Aqua tint Screen The continuous tone requires a slightly different treatment, as it consists of grey tones from white to jet-black. We shall therefore have to expose aquatint grains into the photopolymer film . They are to bind the etching ink in the black and grey areas so that we can avoid an open bite. The first time the aquatint screen is used, it must be calibrated for the ultraviolet light and thus ensure that the final print contains the full grey tonal range of the artwork.

2 3

Development of the photopolymer film in soda solution .

4

5

correctly is the part of your test scale that has been exposed correctly. If the print is a little too light it needs less exposure, if too dark , more exposure. If necessary you can make a new test scale with shorter intervals centred on the best result from the first scale. Make a note of the correct exposure time. If you always use the same printer and always print in 70% (see pp. 68ft), you should now have the correct exposure time for all future halftones. Sources of Error If open bites arise in the darkest areas (which should appear jet-black), y_ ou have either exposed the film too briefly in the UV exposure unit, or your halftone positive has been printed in more than 70% (see p. 72) - if you look at the positive through a magnifying glass on the .light table, or measure the density of the black in Photoshop ori your computer, the darkest areas must only be covered by a 70% dotted structure . If the dots are denser than that, they will close up the image and cause open bites in the jet black areas. Therefore: check the positive before changing the UV exposure time .

6

7 8

Place the laminated copper plate on the vacuum frame. Leave the top Mylar on. Place the aquatint screen on top. Switch on the vacuum, place a lightproof plate or piece of foil on top and turn on the UV light. Move the lightproof plate a little every 15 seconds until you have produced a photopolymer film with an aquatint-screened exposure scale ranging from 15 to 90 seconds. Take out the plate and remove the top foil by rubbing your hand across the edge of the plate. Place the exposed plate in the developer. Use a sponge in the developer as though you were washing the plate. Develop the plate with steady but gentle movements all over the plate until the aquatint grains can be clearly felt. If the development is inadequate, you will not be able to feel them, and if you over-develop the plate, you risk washing away the grains. You must rely on your senses: if the plate begins to appear very coppery in the developer, you will have over-developed it. If the aquatint grains cannot be felt, extend the developing process a little. Take the plate out of the developer, rinse it in running water and check the aquatint grains with the back of your hand. They should be felt like fine sandpaper. If the development is inadequate, develop the plate further until you can feel the grains clearly. Rinse the plate, spray it with white vinegar from an atomizer and gently rub the vinegar into the plate. Give the plate a final rinse in cold water, dab it in a newspaper and let it dry in the drying cabinet. Ink up the plate and print it.

The print will show a scale of grey tones. In the jet-black . area that was given the shortest exposure, you find the correct exposure time. Use the corresponding exposure tinie for aquatint in the future.

53

The aquatint screen is bought ready-made and will last a lifetime, if you treat it properly . A good quality screen .will leave no visible trace of the screen pattern in the final print. 3b. Calibration of the Continuous Tone As mentioned earlier, a continuous tone positive contains a grey tonal range going from white to jet-black . It could be a washing , a photograph , a painting etc. on a transparent film . Before exposing the positive , you need to expose the aquatint screen (see above) . Place the laminated copper plate on the vacuum frame. Place the aquatint screen on top. Switch on the vacuum frame and expose the plate for the optimum time. 4 Replace the aquatint screen with the washing. The first time you expose a washing it should also be calibrated the same way as the aquatint screen by means of a lightproof plate or foil. 5 Take out the plate and remove the top foil by rubbing your hand across the edge of the plate. Place the exposed plate in the developer. 6 Use a sponge in the developer as though you were washing the plate. 7 Develop the plate with steady movement all over the plate . 8 Take the plate out of the developer, rinse it in running water and check the aquatint grains with the back of your hand. They should be felt like fine sandpaper in the coppery (black) areas of the image. If the development is inadequate, develop the plate further until you can feel the grains clearly. 9 Rinse the plate, spray it with white vinegar from an atomizer and gently rub the vinegar into the plate. 10 Give the plate a final rinse in cold water, dab it in a newspaper and let it dry in the drying cabinet for about 5 minutes. 11 Ink up the plate and print it.

45

55

1.05

1.15

1.25

1.35

1 2 3

If the print is too dark with loss of detail or areas of open bite, the washing needs more UV exposure - if too light, less exposure . Unlike the previously mentioned positives , the continuous tone positives can involve a lot of different media , like Indian Ink, gouache , toner

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1.40

1.55

2.15

2.30

Top: Calibrating the Aquatint Screen Bottom : Calibrating the Continuous Tone (Indian Ink Washing)

washings , photocopies etc. The different media all have different transparency and therefore require different exposure. This means that you will have found a guideline for continuous tones , but each of them has to be treated individually. If the washings contain actual lines, the aquatint screen will not influence those lines negatively, and this means that you can always expose lines and washings together - but use the optimum exposure for the washing. The exposure duration for the aquatint screen is always the same .

Materials Photopolymer film Washing soda (Natrium Carbonate) Aquatint screen

4 sec. 2 sec. 1 sec. 0 sec. Flash Exposure: Indian Ink Washing. Artwork: Mette Marott

Adjusting Contrast - Flash Exposure In gravure , the photographer 's rule of thumb applies too: ,,Exposefor the shadows, develop for the highlights". The photopolymer film is able to render even the finest grey tones , but some positives can be so highly contrasted that very light and delicate tones can become too weak when the dark and black are correctly rendered .

built-in timer . The duration (in seconds) of the flash exposure depends very much on the strength of the UV lamp.

2

In such cases, and in case the positive contains extremely fine greys, the photopolymer film may benefit from a final flash exposure before it is developed . Not all images gain from this flash exposure, but if a washing contains e.g. several dark areas with important details in them , the washing as a whole will definitely benefit from such a treatment. Without the flash exposure you can expect a rendering of about 80% of the artwork 's tonal range. With the flash exposure you can expect a rendering of about 9_5%of the artwork 's tonal range.

3 4

Take the plate out of the vacuum frame after the last exposure as if you would develop it, and remove the positive. Place the undeveloped, exposed plate in the exposure unit without vacuum. Expose the plate in steps of 1 second up to 8 seconds. Develop, dry and print the plate in the usual way.

The flash exposure must not be too long , in which case you risk burning out the image. If it is too short , nothing happens. The correct flash exposure will decrease the contrast in the image and produce softer and more numerous grey tones.

In this case it is just as vital to do a calibration test as it was for the aquatint screen and the positive , and it is certainly an advantage if you have a light source with a

55

PHOTOPOLYMER FILM - FOR ETCHINGS

General Remarks As mentioned earlier, the photopolymer film can be used as etching resist when you want the artwork images etched into the copper plate.

Before exposing the photopolymer film, you need to thin it to about 15 microns or buy a ready-made thin photopolymer film of 15 microns.

Many photographers and printmakers wish to etch their photos and drawings into the copper plate, partly for aesthetical reasons , partly for qualitative reasons or because they intend to work the plate further in other ways. Anybody who has experienced having to make an actual photo gravure with gelatine-coated plates will often have been frustrated by the long working process and the difficulty of gaining control of the result. With the photopolymer film it is simple and relatively fast to achieve very beautiful results. The photopolymer technique also gives you the option of additional work on the plate, using acrylic resists as aquatint , soft ground , hard ground, lift ground , etc. Another option could be the etching of a photograph, or a photographic fragment, into an area of an already etched plate (see also lift ground , p. 32ff.).

Photogravure etched BO minutes in tank. Artist: Henrik Beegh.

57

Thinning the Photopolymer Film Remove the top foil and save it for later. Now put .the plate in a fresh soda developer under a lid for 8 to 30 minutes. The developer thins the film evenly all over, except for the edges : they will disappear. The predeveloping time depends on the quality of the water that is, the amount of calcium in the water. This means that a test has to be made once and for all, and the plate taken up and checked at intervals.The moment tiny perforations begin to appear in the film, you will have over-developed the plate by one to two minutes. At the Printmakers' Experimentarium the optimum pre- development takes 27 minutes. When the plate is ready, take it out of the developer and rinse off the dissolved photopolymer film in cold, running water . Dab it quickly in clean paper and put it in the drying cabinet. The dabbing must be swift to keep the paper from sticking to the unprotected film. After drying , back the plate with wrapping tape (seep . 44) and keep the plate in a lightproof box until you are ready to expose it. The pre-thinned plate must be used the same day. The Subject for Etching The image for etching must be either a black and white drawing/painting or a halftone . Continuous tones cannot be etched unless they are transformed into halftones by way of a scanning to the computer (see p. 86ff).

The Black and White Drawing/Painting

2

3

4

5 6

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10 11 The subject for this etching has been found in a book and photo copied onto an overhead film. It was exposed onto the thinned photopolymer film, developed, given an even layer of aqutint and etched 20 minutes. The plate is now ready to be worked further with one or more of the acrylic resists .

58

12 13 14 15

Back the pre-developed copper plate with packing tape (see p. 44), place it in the vacuum frame and cover it with the protection foil you removed before the pre-development. (This prevents the film from sticking to the stencil). Now expose the artwork for ttie time it would have required had it been a non-etching: The aquatint exposure + that of the washing. Place the exposed plate in the developer. Develop very gently with just the weight of the sponge, since the photopolymer film is now ultra-thin. Develop the plate 1-2 minutes with steady gentle movements all over the plate until the image looks coppery. Rinse the plate in cold running water and dip it in ferric chloride for a few seconds. Where the image oxidizes, the copper has been bared. Non-oxidized areas of the image must be developed further, for example by using a cotton bud. Check again and continue till the entire image oxidizes. In this process, it is better to be safe that sorry and check a few extra times: Over-development comes rapidly, and then the image will disappear. Repeat stages 4-7 until the entire image oxidizes. De-oxidize in vinegar and salt (see page 44), rinse, dab and dry the plate in the drying cabinet. If the image contains wide black lines or large black areas that would create open bites in the final print, continue with the next point. If it only contains fine lines that would not create open bites, jump to item 12. Spray on an even coat of aquatint. Harden the plate for about 20 minutes in the drying cabinet. Stop out the bared edges of the plate and harden the plate for another 10 minutes in the drying cabinet. Etch the plate for 30 minutes. Finally strip and rinse the plate (see p. 44). A test print can be made with the photopolymer film still on before stripping. PS. Only washings, photocopies and line drawings containing bold lines have to be coated with aquatint before etching. This prevents open bites. Thin line drawings, halftone photographs , and digital images with halftone dots can be etched without the coat of aquatint .

The Halftone (Photogravure) The halftone functions as a stochastic screen when it is exposed into the photopolymer film . Some areas of the positive are very dark , some are lighter . The grey tone values are made up of the sizes and concentrations of dots in the image . The exposure duration is the same as for a non-etched halftone (see p.52).When we are dealing with etched photogravure , the grey tone range is achieved partly by the dotted structure , partly by the duration of the etching .

2 3

4 5 6 7 8 9

Develop the plate for 1-2 minutes with steady gentle movements all over the plate until the image looks coppery . Rinse the plate in cold running water and dip it in ferric chloride for a few seconds. Where the image oxidizes, the copper has been bared. Non-oxidized areas of the image must be developed further, for example by using a cotton bud. Check again and continue till the entire image oxidizes. In this process, it is better to be safe than sorry and check a few extra times: Over-development comes rapidly, and then the image will disappear. Repeat stages 1-3 until the entire image oxidizes. De-oxidize in vinegar and salt (see p. 44), rinse, dab and inspect the plate. If you are satisfied, dry the plate in the drying cabinet. Stop out the bared edges of the plate. Harden the plate for another 10 minutes in the drying cabinet. Etch the plate for 90 minutes. You can take up the plate for inspection at any time during the etching and continue developing the plate or etching the plate. You can even make a test print with the photopolymer film still on before stripping . Finally strip and rinse the plate (see p. 44).

Photogravure etched 90 minutes in Edinburgh Etch. Top: Proof with bits of photopolymer film still on top of the plate . Bottom: The final print. The film has been completely stripped . Do note the difference between the two prints . The light areas in the bottom print contains plate tone, while the the top print is printing completely white in the light areas because of the photopolyme r film.

Removing the Etching Ground Remove or strip the photopolymer film and stop-out with soda and water (seep. 44).

59

Safety Because the coversheets are in place during most of the handling , there is minimum opportunity for exposure to the acrylates. However, constant and prolonged contact would increase the likelihood of skin irritation .

re-used for any purpose. Care should also be taken to avoid direct contact with the used developing solution . Minimize contact with scraps and used coversheets by disposing of them immediately in a plastic trash bag.

Contact may occur while

•

Trimming the film to correct size Placing film on the plate

•

Developing the film

•

Removing the used film

•

Handling scraps and coversheets .

After the exposure , the Mylar coversheet is removed prior to placing the photopolymer film and plate into the developing solution . Unexposed areas of photopolymer film should not be allowed to touch the skin . Care should be taken when disposing of the coversheets , since they may contain small amounts of residue . Coversheets may contain photopolymer residues and should never be

60

Contact with the film is also possible during its removal from the plate . At this point , the plate is placed in the stripper (see p. 44) . Direct contact with the film and the used developer should be avoided by wearing neoprene gloves similar to dishwashing gloves. Gloves should be changed or washed often to avoid build-ups of dirt and contaminants . They should not be turned inside out. Wash hands routinely before using the toilet , smoking or eating! Any time the skin is directly exposed to unexposed film or developing solution , it should be immediately washed with soap and water. is truly effective.

PHOTOPOLYMER PLATES - SOLAR PLATES

The photograph and the greyscale were printed from a Solar Plate from a .,pre-press stencil" 80%/30 microns (see pp. 68ft). Artwork: Mette Marott.

General Remarks I Scandinavia we have a long-standing tradition of using photopolymer plates (Solar Plates) for intaglio - especially Photogravure. A lot of research has been going on since the end of the 1980s, almost 6 years before the photopolymer filmwas ,,discovered"for intaglio printmaking.

As mentioned earlier, photopolymer plates come in different thicknesses and qualities .The best results have been achieved with PHP Plates, which are backed with thin steel sheeting. It makes the plate stiffer and easier to handle during the copying and developing process as well as the printing process. They are called KM 73/ Printight Photopolymer Plates (the thickness is 0.73 mm/ 0.35 inch). In some countries they are sold under the name ,,Solar Plates". The plates are about 7-1 O times as expensive as the photopolymer film . Handling the Plates In principle , the plates are handled almost exactly like the laminated photopolymer film, though you find differences in the cutting, development, exposure, and

hardening processes. Apart from the logical fact that the image cannot be etched into the plates, I will in the following describe all the differences between laminated film and solar plates, step by step. Cutting the Plates To prevent the plates from cracking, cutting and trimming the plates should be done before the plates are hardened, with a plate cutter or a cardboard cutter . Before Exposure The plates are provided with a thick protection mylar, which adheres lightly to the photopolymer emulsion. Do remove this mylar before any artwork (transparent) is placed on top in the vacuum frame. If a transparent foil has a shiny surface , air pockets may occur between the shiny transparent and the plate . Newton rings may also appear owing to interference between light-rays on the surface of the two shiny surfaces. They will show up as irregularities in weak tones. Powdering the plate with finely grated talc and then brushing it with a soft brush can 61

solve both problems. The remaining traces of talc will ensure that the vacuum will suck out the maximum amount of air between the layers and thus provide the closest possible contact. UV Exposure The exposure times are 4-8 times longer than the exposure times we know from the photopolymer film depending on the light source and the positive. The exposure time for the aquatint screen is normally 1/3 of the exposure time for the continuous tone. As with the photopolymer film, you must make a calibration test first. Remember, if the print is too light you need a shorter exposure time, and if it is too dark you need a longer exposure-time.

Safety • Use rubber gloves while developing the plate .

• •

• •

Discard the protection mylar when you remove it fro the plate. An unpleasant, but harmless smell will emerge during development - be sure to ventilate well. The developer may be poured down the drain after use. Do not touch the unhardened polymer base with your hands.

Development and Drying Development takes place in a photo tray with normal tap water - 20 degrees Celsius. Submerge the plate in the water for one minute without touching it. Brush carefully and gently for one minute with a soft ,,painting cushion" or ,,washing dabber" (like those used by painters to distribute the paint). A sponge is too hard for the very soft surface.

Rinse the plate under running cold water and place it on a newspaper. Now dab excess water away with a firmly wrung piece of chamois leather. At this phase, the plate is extremely sensitive to dust and anything that could scratch the very soft surface. Take care that no water drops are left on the plate as the chalk from the water causes stains when drying - and such stains will be visible in the final print. Finally dry the plate in the drying cabinet for 5-10 minutes. Hardening Leave the plate to harden under the UV light or in the clear sunlight for a minimum of 20 minutes. During this exposure, the soft polymer surface will change to a hard plastic-like surface that can now be inked up and printed.

The plate is strong enough for an edition of more than a thousand prints.

62

Opposite: Print from a Photopo/ymer Plate. Artist: Henrik Baegh.

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CREATING THE POSITIVES

Drawing and WashingTechniques Here we are dealing with a non-etch technique, with which you can achieve litho-like effects by drawing and painting directly on transparent materials. I especially recommend drawing and painting on waterproof drawing foil (as used by architects). When transferring the picture to the photopolymer film, you must expose the aquatint screen first, then the drawing/washing (see pp. 53ff). You can also choose to paint directly onto different types of transparent foils with grains, but as they already contain a dot structure, you must then not expose an aquatint screen, but instead treat the foil as a halftone positive (see pp. 52ft). Using a light table is highly recommendable, as it gives you the advantage of being able to review your work continuously. Drawing and Washing Media Not all materials are equally suitable for this type of work, and the good ones can only be found by trial and error. Experience shows that gouache, lithographic pencils, and wax crayons give good results, while for example many felt tip pens lead to disappointment. A combination of

water-soluble India Ink and black designer's gouache can be compared in quality to a lithographic washing. Airbrush colours and Graphic Chemical Black No. 1659 (as soft ground) are also well suited for the purpose. Black and red watercolour pencils make clear lines and can be washed out with water or spit. Watercolour pencils can also be washed out on different pieces of drawing foil, which are then stacked and finally exposed all at once. Here it is an advantage to work at a light table, so as to get an impression of the final result during the process. You can also expose the foils in each their separate photopolymer film laminated plate and print them in different colours. Toner Washings Used toner from a photocopier makes for some interesting washings. The toner is usually accumulated in a special container in the machine. Be careful not to breathe in the powder while taking a couple of teaspoonfuls of it and pouring it into a glass. Mix the toner with about 4 parts 35'% propyl alcohol and about 1 part Liquid Hard Ground

65

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and stir well. Once the toner is liquid, there is obviously no risk of inhalation. With a brush or some tissue paper you will now be able to make the most wonderful washings on the drawing foil. If you add a little more polish with a brush to an already washed surface, you will achieve exciting effects. While the surface is wet , you can sprinkle on sea salt; when it has dried, you can scratch up the washing with steel wool or various tools and thus create a variety of textural effects. UV Exposure The washing must be completely dry before it is placed in the vacuum frame for UV exposure, otherwise you risk that it sticks to the photopolymer film and is ruined.

The various drawing and washing media do not have the same level of transparency , and the optimum standard exposure time is therefore only useful as a guideline . Under-exposure will result in a very dark print, correct exposure will give the print a full wealth of detail , and over-exposure will burn out all the details. Flash-exposure may be of vital importance here (seep. 55).

66

Top left: Differet wash media on drawing foil - 11/uair brush color India Ink - Badger Acrylic Aquatint. Top right: Differet wash and drawing medias on drawing foil. Bottom : Preparing the art work on a light table. Opposite: Toner Washing. Artist : Leif Lage.

Left: Handmade stochastic screen Right: Epson's (Stylus Color 1520) screen 65 lines per cm

Digitally Generated Stencils General Remarks The personal computer and Adobe Photoshop have in later years replaced the conventional darkrooms .The final blow, as far as the printmakers were concerned, was struck by the film manufacturers, when they stopped producing lith film and the special developers used for lith film. These products used to form the basis of photogravure - today, the name of the game is scanning and digital imaging (see appendix II, pp. 85ft) .

The lucky outcome of this development is that all the darkroom work in connection with intaglio can now be carried out in a far more exact and completely Non-Toxic version as compared to earlier . And what is absolutely essential: No matter what you create on your computer screen: text, photos , drawings , washings , collages , etc. , the right equipment enables you to print such images out for copper prints in a quality which compares favourably even with that of professional pre-press bureaus (see p. 70) - and at a cost of about a tenth of their price .You can

68

print the screen image as a halftone or a continuous tone on transparent inkjet printer film. You can print out in duplex to be plate-printed in two colours , or you can print out several layers separately and print the plates as two-, three- or four-colour prints from separate copper plates. Your options are practically unlimited . The Printer The print should be made on transparentfilm for ink-jet prints. The cheap ones you get from office suppliers are less sensitive to dust than the expensive Epson inkjet films and far easier to handle.The printer must be able to print from a separate black ink cartridge . Some printers are better than others for this purpose. The ink must be jet-black, the print quality 1440 dpi (dots per inch). The dot-structure from the print heads differs from one printer to the other. In the Printmakers' Experimentarium we have obtained excellent results with the Epson Stylus Colour 1520 and 800. The dot-structure corresponds almost exactly to the handmade stochastic dot screen we produced for photogravures made in the darkroom. In general, stochastic screens will give you more beautiful results than conventional screens.

Printing the Halftone Once you have calibrated your halftone positive to the photopolymer film, the exposure time and developing time never vary (see pp. 52ft), because the image is translated into a dot structure in which the blackest part is always exactly 70% - (80% for Solar Plates) . The point of departure for the procedure described in the following is that by using Photoshop 7.0, you have created and finished a screen image that matches the intaglio print you intend to make.

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Click File ->click Print. You are now in Print. Choose printer, choose paper format , choose orientation (Portrait or Landscape) , then >click Properties .

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If you do not have access to a suitable printer, you can always save the file on a CD and have the image printed out at a pre-press bureau. For photopolymer film you must save the image in 70% and print out with a stochastic screen in 40 microns . For Photopolymer Plates/Solar Plates you must save the image in 80% and print out with a stochastic screen in 30 microns. This difference is due to the fact that the Solar Plate renders more datail in the image.

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You are now in the Image Size dialog box. What it says inside the frames does not matter . Click away the tag under ,,Resample Image". Now try filling in different values for ,,Resolution" and notice what that means to the height and width of the image. If you put ,,300" under ,,Resolution", you will immediately be informed of the optimum printout size of the image in centimetres or inches. This means that you need to have a fairly good idea of the size of the final intaglio print when you are scanning in images. There is no harm in having too high a resolution when you are scanning - you can always lower it in Photoshop later, but it will cause the scanning process to take longer and the image to occupy more space in the computer 's memory and on the hard disc , if you choose to save it. If, however, the scanning resolution is too low compared to the size of the final print , it could have dire consequences. When you are scanning a colour image , which you intend to use as a greyscale for intaglio, you must scan it as a colour image - you will change it to greyscale in Photoshop later. A black and white negative is scanned as a greyscale from the beginning . This also applies to images on paper, which are scanned in on the flatbed scanner .

The Perfect Negative for Photogravure For photogravure of black and white negatives I recommend: I/ford XP2 Super film or Kodak T400 CN. The films are black and white , but they can be developed at any tourist shop offering ordinary colour development as ,,One-hour service ". The films render images with exquisite softness and beauty , and these soft tone transitions are very important to the final intaglio result. These films are no less than perfect for photogravure , for the experienced photographer as well as the learner . They are ,,born" as 400 ISO films (the speed) . Because of their extensive tonal range , however , they can be exposed at any speed from 50 to 800 ISO, and no special attention need be paid to that fact when the film is developed. In practice , then , this enables you to expose the pictures on the same film at different speeds (from 50 to 800 ISO) and subsequently have the whole film developed as 400 ISO. No other black and white film can do that without causing the quality of the negatives to suffer certain losses.

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The Flatbed Scanner Some flatbed scanners •r ON s, ,n M"" 3 5enr,g: are made so that they ,_ 3 can also scan films, and __ J~ they largely work in the :l same way as film Doci.,wtT~ fllll'IType IPowYeFtn scanners. Flatbed 3 scanners, however, are [,,,,.(do 3 !.Jl-o-T,'PI' normally used for ..,., scanning pictures, ,;J ::J.c..J photos, washings and Aiturtrren1, drawings. Again, the scanning resolution .l.Jf:1 UndwpMClick File in upper left corner >click Open >Click View >click Fit on screen. Re 2 Change Mode: The ,,Change Mode function is found under ,,lmage">"Mode". Click Image >click Mode >click Greyscale and confirm ,,Discard Color Information".

The following presentation presupposes the digital existence of the image in question, either on CD or on the hard disk. I will take you through the most widely used tools for creating the perfect positive for intaglio. The working process: 1 2 3 4 5 6 7 8 9

Open Image Change Mode The Crop Tools Levels Adjustments The Healing Brush Save as Master Image File Format Image Size Sharpen Image

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tzi ZoomTool ------------. Remember that you can enlarge any part of the picture when the magnifying glass is selected, simply by clicking with the mouse. When you want to shrink the image, hold the ALT key down and click with the mouse.

The image has been opened, changed to greyscale and activated to fit on screen.

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The Photoshop Crop Tools are found in the Tools palette (3). Click and drag to define cropping frame. Simple Cropping The program darkens the part that is about to be trimmed off. This enables you to see how the image is going to look , before you actually crop it. You can use the mouse to make delicate adjustments before you cut anything off . The dark area helps you determine where to draw the final line .

Tips: Two ways of cropping the image : • Press the Enter key

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Double-click on the part of the image you want to keep.

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Left: Preparing the Cropping Above: The Cropped Image

89

Re 4 Levels Adjustments

The Levels adjustments is found by selecting Image >Adjustments>Levels . This opens the Levels dialog box. The diagram shown in the dialog box is the histogram of the image. It shows you how the tones in the image are distributed with the shadows on the left and the highlights on the right. X

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If the levels are bunched up towards the left that is a sign of shadow clipping. The dialog box reveals that the image lacks shadows. There are no pixels darker than about 22 (see also the Levels dialog box p. 91). This causes a lack of detail in the black areas.

You work visually with the levels. This means that as you adjust the levels , the image on the screen will change . If it does not, it is because you have not selected Preview in the dialog box in the lower right corner . The Shadow and Highlight Sliders When you move the shadow or highlight slider under the graph , you alter the contrast of the image . If, for instance, you move the highlight slider towards the left, Photoshop will turn the lightest areas of the image white . At the same time , all the remaining pixels are distributed evenly to

90

cover the tonal range from Oto 255. In other words, the darkest areas remain more or less the same, while light areas become lighter.The same happens when you move the shadow slider towards the right. Now the darkest pixels turn black , while the white remain white. The Gamma Slider The gamma slider placed exactly at the middle adjusts the midtones of the image. If you slide it towards the right , the image will grow darker, because you are expanding the dark end of the image. This gives you more details in the shady or shadowy areas . At the same time you are squeezing together the light end, so that you get fewer details in the highlights.

You generally use the gamma slider for final adjustments of the light. Thoroughgoing changes here are best avoided , as they tend to lower the quality of the image.

The first adjustment consists in moving the shadow slider to the right. This causes the image to grow darker . In more accurate terms , the darkest areas in the original image become black .

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Re 5 The Healing Brush

. - ~..1 One of the new tools in Photoshop 7 is the Healing Brush. It is used in the same way as the cloning tools, but its effect tz1'. is different , in that it matches the texture , lighting , and shading of the sampled 5 pixels to the source pixels. This feature .l makes the tool very usable, for example if you want to remove specks of dust , hairs or the like from a scanned-in image. The brush constitutes such an

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'I A closer inspection has shown this scan to be full of little flaws (dust etc.) Specks of dust can easily be removed with the healing brush.

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improvement for this type of task that you will not know how you could ever do without it. You find the healing brush in the tools pallette (5). Begin the process by holding down the Alt key to choose an area to sample from .

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I always work with what I call a master image . I place all master images in a special folder. When the picture is in the computer , I inspect it to see if it needs any changes. If not, it is put directly in the master image folder . If it does need adjustments , I only do the following (what we have done until now) :

• • • • •

Change mode to greyscale Do cropping Adjust the contrast Retouch any dust marks or scratches Then I save it in the master image folder . In this way I make sure that all the master images are just the way I want them , and that I always have an original copy in the master folder of any image I work with elsewhere.

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