Tuesday, December 30, 2008

A Treatise on Photogravure

The Internet is a wonderful place. Really.

I am carrying around on my vacation a 1974 reprint by the Visual Studies Workshop of Herbert Denison's A Treatise on Photogravure (in Intaglio by the Talbot-Klič Process). It is available used at a price of $275 (for the reprint) at Amazon.com today, which may put it out of many people's reach.

For whatever reason, this book is one of many scanned by Microsoft as part of an effort to put out-of-copyright works on the web for wider access. A full color PDF version of this black and white treatise is available, and other formats are available also, in a scan from the University of Toronto. It was the 32nd hit on Google.com that yielded a launch page on Archive.org to find a scanned version of the text. I keep forgetting to search there first - they have several other early texts on photography.

A brief biography of Jon Goodman mentions that he carried this slender 140 page reprint around with him during his early studies of photogravure in Europe (though it incorrectly lists the first publication date as 1865 - some thirteen years before Klič perfected the method). 

The book presents a complete description of the steps of process in the table of contents:
  1. Introductory
  2. The Negative
  3. The Transparency
  4. The Gelatine Resist
  5. The Copper Plate
  6. The Ground
  7. Mounting and Developing the Resist
  8. The Mordant
  9. Etching the Image
  10. Photogravure in Line
  11. Printing from the Plate
  12. Afterwork on the Plate
  13. Steel-facing the Plate
  14. Historical Notes
The text assumes hands on knowledge of traditional silver photography and darkroom work, and perhaps a working knowledge of carbon printing methods. I do find it amusing that these older texts have sections titled Historical Notes. The facsimile edition reprints the 1895 version - some 55 years after the invention of photography. Also, as others have noted, steel-facing is a misnomer, the copper plates once etched are iron-coated electrolytically. There are some modern references I'll dig up to non-toxic (less toxic) approaches to copper plate photogravure - do poke around a bit to find those.

So if you were looking for something to read as you entered the New Year, this is my recommendation.

Monday, December 29, 2008

Wash out

Let's talk about washing out the Toyobo KM73 photopolymer plate.

On Jon Lybrook's recommendation I eventually purchased the Boxcar Press brush. Dianne Longley talks about any flat soft bristle brush being usable for washout. After constructing my own using taped together bristle paint brushes from Home Depot, I decided to buy the Boxcar brush. At 4" x 8", it fits neatly in the palm of my hand. The soft bristles present a flat broad washout surface to the plate. A plate washer I saw at Kala Institute during a workshop had a large flat brush with bristles about 1" long if I recall correctly.

As Jon and others have suggested, I line the bottom of a plastic tray with a 60 mil magnetic sheet to hold the steel-backed KM73 plate still during washout. I fill the tray with tap water to just near the top of the Boxcar brush as it rests against the bottom. The water is about 70 deg. F. I do not at this time worry about the temperature of the water greatly. I keep my darkroom at about 70 deg. F also.

After first exposing the plate to the positive, and then to the aquatint screen (talcing and brushing the plate before each exposure), I place the plate into the water and allow it to settle centered on the magnetic sheet.

I fire off a two minute timer - my washout for a plate about 8" x 10" is two minutes. Following Longley's suggested wash out procedure in her book Printmaking with Photopolymer Plates, I brush the plate in a circular motion, moving from one side of the plate to the other. I think I am making 3" to 4" elliptical motions with my hand during washout. I make sure to extend the brushing about two inches beyond the plate edge when starting to ensure I wash the entire plate.

I do not put much pressure on the brush. I start by letting the weight of the brush apply the pressure, and add a bit more with my hand. The brush moves across the plate easily - though you will quickly feel friction from the "etched" areas of the plate and the bristles find a hold in the depressions that will later hold the ink. After doing this several times I think that fine bristles are probably important for washing out plates made with a fine aquatint screen.

When I reach the other edge, again ensuring I brush two inches past the plate edge, if necessary I shift the brush down, and continue brushing with a circular motion, overlapping the strokes to the other end of the plate. 

If the plate is long you may repeat this motion, reversing at the edge of the plate one more time.

Jon's site mentioned keeping a stroke count to ensure a uniform wash out. In trading e-mails with him he mentioned he is a bit more relaxed about the stroke count. That said, here is a conundrum. You really want to uniformly process the plates each and every time to get consistent results. If you use different size plates (for different size prints) this becomes interesting. I have been using 8.5" x 10" plates (cut down from larger originals) during my calibration and testing. I'm not sure what I will do when I tackle larger plates. This might be the basis for the warning on the Boxcar site to only use the brush for plates up to 9" x 12".

When I reach the end of the plate I rotate the brush 90 degrees and begin brushing along the other axis of the plate. I vary the orientation of the brush to ensure lightly scrubbing the plate in a fairly random variation. Truth be told, I then rotate the brush 45 degrees and attack the plate (gently) on a diagonal axis.

And then I repeat until the two minutes are up. Note I have read many recommendations for time to wash out. The time recommended is less for relief printing, more for fine halftone work. I do not pre-soak. And I use a soft brush with gentle pressure.

I lift the plate out of the water and, using a garden hose sprayer head set to a broad spray pattern (not a jet) on the end of a hose, I wash the plate down with a fair bit of water pressure. I make several passes over the plate with the sprayer.

I let the plate drip dry for a few seconds before laying it down on a sheet of blue shop paper towel for drying.

The polymer plate is delicate at this stage. The polymer is only partially hardened. I take care to not touch the surface of the plate with my bare hands, nor scratch it with fingernails, the hard handle of the brush, or knock it into anything as I move it around. There's no repairing it once scratched.

Saturday, December 27, 2008

Paul Strand

I just finished watching the documentary Strand: Under the Dark Cloth. The commentary went "[Late in life] Paul Strand went to Ghana... where he used a handheld camera for the first time." Yeah, what looks to be Graflex RB single lens reflex

Cataracts waylaid him briefly in his old age but still he printed - trying to direct his wife Hazel in the darkroom (operations restored his vision and he never drove again, but immediately returned to the darkroom).

Paul Strand was a much younger contemporary of Alfred Stieglitz, and the young Strand at first emulated the pictorialists he saw at the 291 gallery. He later moved to formal abstractions in his images and helped define early American modernism in photography. There is an interesting write-up on the Metropolitan Museum site.

Strand looms large in the world of photogravure. Stieglitz's seminal magazine Camera Work reproduced several of Strand's images in photogravure, the final issue being devoted almost entirely to Strand's work. The quality of the photogravures in Camera Work is said to be outstanding.

In 1940, Paul Strand issued a portfolio of twenty photogravures entitled Photographs of Mexico in an edition of 250. In 1967, Strand reissued the work from the original steel faced copper plates as The Mexican Portfolio in an edition of 1,000. Published by Da Capo Press, with the photogravures printed by the Andersen Lamb Company, of Brooklyn, on Rives BFK paper. Beth Moon observed when we sat down to view them with Mark Nelson and his friend Richard that the photogravures seemed to be varnished. Mark later found a reference to a letter by Strand confirming this. The above note indicates the varnish used in the 1940 edition has in many cases since darkened. The varnish in the 1967 portfolio in my possession seems quite clear. Aperture has available six of the images in an edition of 350 printed by Jon Goodman, from the original plates.

I picked up the 1967 portfolio (said by Strand in the preface to exceed the quality of the 1940 edition - but perhaps that is marketing) to have an example of outstanding photogravure work to set a goal, that is probably unachievable by me in my lifetime, of quality for the process. 

Various searches on Google yield interesting articles about Strand and photogravures. Anne Hammond's article on Photographic Art and Gravure and Letterpress: A Comparative Study of Paul Strand and Ansel Adams being worthy of a read. A reprint of an article about Jon Goodman by Andrew Wilkes that appeared in Aperture #133 is also worth reading.

I first saw a reference citing The Mexican Portfolio as an outstanding example in photogravure in the excellent text Copper Plate Photogravure: Demystifying the Process.  Amazon.com indicates I purchased that text on July 5, 2007. I wonder what led me to do that?

Sunday, December 21, 2008

Printing the Crown Point Press Way

I've come down with something and am mostly staying warm and catching up on reading.

Jon Lybrook mentioned in passing that Crown Point Press was having a sale, and that he really loved their books. I have to say, if it wasn't for Jon's whole-hearted recommendation I would, as a rule, pass up books whose titles start with Magical Secrets About... I went to the web site and on his recommendation bought the three book set. In for a penny, in for a pound. Had I not bought the books, I would have been the poorer for it.

In my search for texts on polymer photogravure I have cast far and wide. There are a few texts on copper plate photogravure of note which I may speak of in the future. But I noticed in my searches that there were some texts for etching that were very relevant in describing technique that could be applied to photogravure.

Magical Secrets about Line Etching and Engraving: The Step-by-Step Art of Incised Lines, by Catherine Brooks is perhaps the most relevant of the three to photogravure. As of today it is on sale from their web site for $46.80 - and it's a steal for that price. The hidden gem inside, that immediately distracted me from Brooks's excellent text up front, is the appendix by Kathan Brown describing the Crown Point Press Way of Printing. Brown, the founder of Crown Point Press in 1962, expounds the view that the artist expresses themselves in the plate, while the printer is responsible for printing the plate consistently. This philosophy is well-matched to photogravure where the making of the plate is the fundamental expression of the image.

That said, I have repeatedly read that the inking of the plate itself is a craft, and it is here where Brown's appendix really gets going. Brown crisply and practically describes how to do that in a repeatable, straightforward fashion.

But that's not all folks, if you order today - oh, sorry, was getting carried away.

Tucked into the front cover of the book is a DVD that includes a 46 minute video of Brown demonstrating the techniques described in the appendix. What an eye opener it is. I have to say, I had no idea what it was supposed to look like when you wiped a plate. Brown demonstrates wiping a copper plate - I have no idea what the practical difference is when wiping a polymer plate. That said, I've paused making my (hopefully last) calibration plate as I review the video and re-read the appendix to try her inking and wiping method. The Magical Secrets web site has additional tips and information.

I bought barrier cream to keep the ink from under my nails (and promises softer hands to boot) and chalk dust for that final hand wipe as Brown suggests. I have a hot plate to warm my Toyobo KM73 plate when inking. I'm poised to try this method.

A hand wiped plate is considered to be the apogee of the printer's art, and involves leaving plate tone (tone in the highlights) that is removed during other wiping approaches. Lybrook I believe mentions that some of the pigments in inks should be considered toxic, so hand wiping the Crown Point Press way is not without its challenge.

In for a penny, in for a pound as I often say.

Monday, December 15, 2008

Annals of My Glass House

Julia Margaret Cameron is a hero of mine. She is an inspiration to follow one's passion no matter when in life you find it, to find supporters for one's endeavors, and to make progress in the pursuit of art through determination and hard work.

The Internet is a great resource for photography and opens up many early sources if you know to look for them. One interesting find is the brief unpublished record of Cameron's first ten years in photography - Annals of My Glass House. She is disarming in her practical approach to setting up a workspace for her new hobby:
I turned my coal-house into my dark room, and a glazed fowl-house I had given to my children became my glass house! The hens were liberated, I hope and believe not eaten. The profit of my boys upon new laid eggs was stopped, and all hands and hearts sympathized in my new labour, since the society of hens and chickens was soon changed for that of poets, prophets, painters and lovely maidens, who all in turn have immortalized the humble little farm erection.
The "glass house" is of course the natural light studio in which Cameron created many of her images. Her nonchalant brush off in her brief memoir of the rejection of her work by some conservative bodies then governing photography and instead focusing on her achievements and progress is refreshing. 

She seems to have two major subjects for her photography, constructed scenes such as Whisper of the Muse, and intensely psychological portraits. Her portrait of John Herschel is powerful, immediate, and piercing in its gaze on her mentor and friend. Her unconventional focus technique, her closeness - bordering on intrusiveness - to her subjects, and her unwavering vision make her portrait work speak more to our sensibilities today than to her near contemporaries who quickly forgot her.

Cameron emerged from obscurity in the 20th century, and her work can be seen in many collections.

Thursday, December 11, 2008

The Book of Alternative Photographic Processes

While Arentz's work is phenomenal in its focus on Platinum and Palladium Printing, on the other end of the spectrum is a compendium covering many alternative processes. Perhaps the most comprehensive recent text is Christopher James's satisfying The Book of Alternative Photographic Processes.

Christopher James seems to be a throwback to the early, heady days of the practioner/technician/instructor. His book goes between the history, the art and the making of images by a wide variety of processes much as texts published by Scovill and others did at the turn of the 19th century. The history that James has to draw on is quite a bit longer however.

I must confess that I am a devourer of history and the people that make it. Maybe it was in James's first edition that I came across the reference to Anna Atkins in the chapter on Cyanotypes. Regardless, James does the material to right by acknowledging the priority of Atkins's lovely work British Algae: Cyanotype Impressions.

Profusely illustrated, with many examples of work in the respective processes (which the reproductions suggest but in no way replace the need for you to see original images printed in the process to fully appreciate their beauty). 

James keeps the tone light and the pace snappy. The format is clear (identifying alternate methods, and the material needed listed up front followed by detailed if humorous instructions):
16 large eggs
Whip the egg whites into stiff peaks (like the top of a Starbuck's latte). If you are being true to this idea of tradition, you will be using a bundle of quills to whip the albumen. If you don't have time to pluck a goose, use an electric blender wand.
This reader will never be able to try all these processes - but I'm certainly going to have fun attempting to do so.

Wednesday, December 10, 2008


I spent this evening completing calibration of my polymer photogravure process. Using Mark Nelson's PDN system I generated process correction curves for the Toyobo Printight KM 73 plates, Rives BFK paper and Charbonnel Universal Black.

I was trading e-mails with Jon Lybrook over the course of the evening discussing Takach's synchronized pressure system (I love it), aquatint screens, exposure times, Kreene, and my printing problems. I must say that uniformly I've found workers in alternative photography processes to be generous with their time and advice. Jon is no exception.

I created two digital negatives on my Epson 3800 printer with two different contrast curves to make polymer plates from and decided to let them dry overnight. I broke free and tackled a homework assignment for my Fine Art Photography class at the Academy of Art in San Francisco, where I am pursuing (albeit slowly) a BFA in photography. My teacher, Cissy Spindler, gave us an assignment to explore visual dynamics and personal expression using paints, pens pencils, pastels etc. to create a drawing/painting/collage - abstract or representational. I read the assignment and went "Huh. Didn't I go into photography specifically because I can't draw/paint/collage my way out of a paper bag?"

Necessity (and a good grade) being the mother of invention, I decided on an abstract that also was educational. Using a palette knife I artistically created color trails of the Charbonnel inks I bought to take for a spin in photogravure. As Jon observed, this was a reason to pursue this process - the wide variety of inks and fine art printing methods available to the practitioner.

From left to right the inks are:
  1. Prussian Blue
  2. Carmine Red
  3. Vermillion Red
  4. Sepia
  5. Burnt Umber
  6. Van Dyck Brown
  7. Universal Black 55981
  8. Gold
I was struck by several things. Foremost how "black" Prussian Blue is. Very dark, very moody. No happy sky, robin egg blue. I'm going to love this color. Second, the reds - very fluid, Carmine Red being more the red I expect to use. Sepia has promise - a strong black brown, the Burnt Umber and Van Dyck Brown seeming weak in comparison. The Gold has an entirely different, coarser texture. I anticipate a challenge not only in finding the images suited to print with Gold, but working with this ink in general.

Charbonnel has a great booklet on their inks that does not seem to be anywhere on-line (but I'll keep looking - oh, try these pages). Haunt your local brick and mortar art stores - that's where I picked up mine.

I converted my painting to black and white to remind me how much I often love colors.

Tuesday, December 9, 2008

Early Morning is for Printing

I woke this morning at 6AM to catch up on printing, turned off the clock and slept for another hour. That said, at 7AM I went to my darkroom, trimmed a steel backed Toyobo Printight KM 73 photopolymer plate to size using a sturdy 18" Dahle guillotine paper cutter (using the polymer plate on the bed which retains the flat edge on cut), and printed my PDN calibration tablets and a Stouffer 31 step tablet once again (1m 10s for the positive exposure, 1m 15s for the aquatint screen) to zero in on my standard exposure time for my UV box from Edwards Engineered Products.

Kim Weston told me several years back when I first met him that he wakes at 3AM to do his printing for the day. Having stayed at Bodie House (where Charis Wilson wrote many of the words that accompanied Edward Weston's photographs in books like California and the West), I can certainly attest that Kim was completed printing the previous day's negatives by the time I stumbled for a cup of coffee at 7:30AM. He has been printing early in the morning since the days when he assisted his father Cole and his uncle Brett in the darkroom.

Printing is a quiet time for me, and something I do alone. Compared to the digital darkroom, the traditional darkroom - and more so the very traditional alternative process darkroom (or incandescently-lit-room) - is a very tactile experience. Cutting, paper texture, brushing and cleaning of surfaces, liquids (use gloves please), printing frames, brushes, scrubbing, washing etc. I find it quite engaging in a fundamental way. And I always feel closer to the work compared to my time spent digitally printing.

I have done most of my darkroom study with Kim Weston. I remember much of what he has taught me. There's a dry side and a wet side to the room. One hand is dry, one is wet when transferring across. Clean towels in the middle, wash your hands and dry them thoroughly to avoid contamination of materials. 

Watching Kim work is fascinating. It became second nature to him long ago - efficient, directed, fluid like his shooting with an 8"x10" camera. Kim shoots in the studio with natural light, so printing in the early morning fits. You have a chance to look at previous day's work, and have the daylight hours to shoot some more.

So, those quiet times early in the morning are a time for printing.

I have noticed that photographers by and large who print their own work early in the morning are also accomplished nappers.

Sunday, December 7, 2008

Platinum and Palladium Printing, Second Edition

Though someone may comment to tell me I am wrong, it is my feeling that while there are many good texts that describe a variety of alternative photographic printing methods, there are few texts that are comprehensive on one method. 

Leading the pack in the latter is Dick Arentz's Platinum and Palladium Printing, Second Edition. While the first edition was a very good text, the second edition is that rarity of where the improvements are welcome and justify purchasing that second edition even if you own the first.

What makes a great textbook on an alternative printing method? A much needed introductory chapter, that appears in the second edition, whose purpose is to get you to that first print. It may not be the best print you ever made, but it certainly simplifies the detailed discussion of the process once you make it from start to finish. Everything becomes very clear.

Another point that makes a textbook useful is that the material can be applied to related processes. The comprehensive chapter on paper, covering solutions to common problems associated with using a particular paper for platinum and palladium printing, surveying some major available papers, and describing their artistic properties is valuable for many other processes. The material on sensitometry is applicable to all photographic processes. Similarly the discussion on UV light sources, coating methods and equipment, appendix on digital negatives, and other material will prove valuable to all your alternative photographic endeavors!

Arentz writes in a crisp, no nonsense style with the rare humorous remark (maybe someday I should write a blog suggesting The Elements of Style by Strunk and White as an allegory for creating an image - Arentz's spare prose hearkens back to that practical guide).

I use Mark Nelson's Precision Digital Negative system to make the contact negatives needed for Palladium printing. I have settled on the Na2 method of contrast control. The paper I use for this process is Bergger COT 320 - expensive but beautiful, and great wet strength to make it through the clearing baths and archival wash.

I find myself going back to this book every few months, and leafing through the material. Something will make a bit more sense than it did when I started all this. A comment might clarify something I'd noticed.

The platinum and palladium process is not that difficult - and the results can be beautiful. Armed with this book, and Mark Nelson's method for creating digital negatives, the process can be simple and enjoyable!

Exciting times in Landscape Photography

If there is an exciting time for landscape photography it is sunrise or sunset.

It's 5AM and I'm thinking about Alain Briot's dictum to "Focus." It could well apply to me eyes at this moment and my wish for some psychoactive drug like caffeine to make me bigger, stronger, more awake.

Here in Death Valley I've once again had the opportunity to wonder "Where are all the people at sunrise?" I see lovers holding hands at sunset - perhaps they are still in bed exploring other landscapes?

Lighting is critical in photography. Not only does the lighting change over an hour (soft light before dawn included), but the times also provide a low angle of incidence helping model the landscape in patches of shadow and light, bringing features to relief. At midday the same features may appear flatter in a photograph with less useful strong contrast that fails to add depth. 

Mapping a 3D world on to a 2D representation in a photograph requires some thought to make it work best. And shadows - the flip side of light - are your friend. Other visual clues help suggest depth in your photograph - size relationships, aerial perspective, and tone.

I will say this though, more than any other fine art photography genre, landscape photography builds character.

I'm late.

Saturday, December 6, 2008

Alain Briot

"Focus." Alain Briot replied when I asked him what it takes to be a great landscape photographer. In all senses of the word. Alain's work testifies to his intense focus to producing unique and beautiful landscape images.

In discussing creativity he remarked, as I've heard others, that it's increasingly hard to find a place that's never been photographed before. The challenge is "seeing a place in a way someone hasn't seen before." He had made an earlier comment regarding people buying art because "we want someone else's view of the world."

Alain has a great web site called Beautiful Landscape. He has many essays on that site covering all aspects of photography from creativity and personal vision to marketing and selling your work. Alain is very articulate - not a requirement for a visual artist, but very helpful for those wanting to learn more.

I've taken several of his workshops, and studied with him privately. He broke me in to using view camera movements for landscape photography. Natalie Briot, his wife, assists and runs the workshops and brings a visual artist's background to the experience for all participants.

During a print review today, Alain showed some of his recent abstract landscapes where he intentionally moved the camera during the exposure. The images were exquisite, forcing the viewer to focus on the light and the colors as opposed to the details. He asked the workgroup participants to try the exercise during the workshop to relax and flow into a pure creative process and move away from viewing landscape photography as always sharply technical. If only to try it out.

I'm writing this post from a workshop with Alain and Natalie in Death Valley National Park. As a fellow student was telling of a rather harrowing experience getting separated from a group in a workshop in White Sands, I suggested to Natalie and Alain a new tag line for their workshops - "We've never lost a student!" But then thinking back on a quote from our current governor in California in the movie Terminator 2, I thought "Come with me if you want to live." would be a catchier phrase.

Tuesday, December 2, 2008

Why do alternative processes?

A common question asked is "Why do alternative processes?" I suspect the answer is very personal to each artist.

I'll take one thing off the table immediately - you don't explore alternative processes to simplify and streamline your life to free up time for other activities. I was musing during a workshop with Larry Shapiro that taking on oil printing as a process could easily fill any spare time I had left. 

If you want expediency, volume, and color - consider a digital camera and printer. I use them for my color work.

My interest in alternative processes is idiosyncratic.

First, I think alternative photographic processes allow you to express a print in a seemingly endless variety of ways. The processes are not for someone who wants to quickly produce many copies of single print. In many processes, there is a craftsman approach to the print, with handwork (as in oil printing) making each print unique. The multitude of processes allow for a wide variety of papers, pigments, emulsions, and application methods for expressing one's artistic vision. Something for everyone. 

Second, the processes are physically engaging. Frankly, sitting in front of computer (which I do a lot of) doesn't excite me. In fact, I spent a great deal of time studying efficient digital workflows and printing with the goal of spending less time in front of a computer and more time making images. I find alternative processes very tactile - textures and liquids and action - the direct physical connection to the process influences my approach to image making. I like playing with this stuff!

Third, I am fascinated by the history and the accomplished practitioners of the various processes. When I do a cyanotype, I'm thinking of John Herschel, of Anna Atkins, and John Dugdale. It adds a depth to my approach, it influences my shooting when I anticipate expressing the print in a given process.

Fourth, I find alternative processes intellectually stimulating. Detailed knowledge is required for some processes and I find it stimulating to "crack the code" and work towards mastering it. I've been scouring the web for used original source books from the late 1800's that describe the processes from the early practioner's viewpoint. Hazardous materials wasn't much of a concept back then seemingly (can you say "uranium toning"). 

I'm just beginning on this journey really. 

Monday, December 1, 2008

Polymer Photogravure - Closeup of the inked plate

The Toyobo Printight KM 73 plate is a steel backed photopolymer plate. It is used primarily in the letterpress industry for commercial applications.

As the catalog on Anderson & Vreeland shows, the KM series comes in a variety of thicknesses, and the plate is harder after processing than other types of plate.

The KM 73 plate can reproduce halftone images up to 200-lines/inch according to the documentation.

The random aquatint pattern imaged on to the plate to the left in the second exposure was accomplished with an 1800 dpi screen purchased from T and R Graphics in Colorado. They worked with Jon Lybrook to create the stochastic, aquatint screen specifically for his use in polymer photogravure. Jon suggests asking for Rick Williams and mentioning his name.

The ink I am using is a classic Universal (Soft) Black etching ink #55981 from Charbonnel. It is available from a number of suppliers. Graphic Chemical and Ink Co. also make a respected line of etching inks. Etching inks have a consistency and pigment designed to work with well in how the ink is lifted by the paper. There are many varieties of black ink from each manufacturer, and many varieties of ink (an enormous color range is possible which is one of the primary attractions of this process for me).

On the right you can see the same magnified area of the plate after inking. The numerals are raised and were cleared in the wiping - the black areas are textured from the aquatint exposure and hold the ink for printing.

I am musing that the photogravure process is demanding and a bit more complex than other alternative processes as you not only have to produce a well-expressed print (the plate) from the original image (what would for other processes be your negative) - but then print that plate as a traditional etching printer would. I've seen references to master plate makers distinguished from master printers - and Jon Lybrook recently made a notation on his excellent site describing polymer plate photogravure that:
The better plates we produce, the more an expert level of skill as a printmaker is required to render the subtleties and details contained in the new plates.
If you were looking for an alternative process to pursue that had a depth and potential for a lifelong learning experience, this may be the process for you!

Starting with Polymer Photogravure

Forget my last post where I said I would be doing cyanotypes. That's a story for another day.

I got distracted doing some initial work at home with photopolymer gravure, or polymer photogravure, or photopolymer etching. This is a process I really want to get my arms around. Let's start with some basics.

Photogravure is an intaglio process perfected in part by none other than William Fox Talbot - the inventor of the negative/positive photographic process. He is not to be confused with Lawrence Talbot. The Talbot-Klic process, as we know it today, was defined in 1878. Traditional photogravure employs a polished copper plate covered with a photo-resist that is chemically etched to create an intaglio plate for printing.

Photogravures can be beautiful. Paul Strand's Mexican Portfolio is considered an outstanding example of the art. Alfred Stieglitz published many beautiful photogravures in his seminal periodical Camera Work.

A new method for doing gravures is possible with photopolymer plates. Developed for the commercial printing industry, photopolymer plates are UV sensitive and harden when exposed. Placing an positive image (such as above) in front of the plate will produce a photographic relief on the plate. I will go into this in a bit more detail in a later post, but to get an image suitable for printing it is necessary to do a second exposure with  an aquatint screen. The screen is essentially a random halftone pattern  that eliminates "open bite" (large inked areas with no texture in the plate to hold the ink).

The plate I am playing with is the Toyobo Printight KM 73. The Toyobo site has a summary of the platemaking process. Add the second exposure with the aquatint screen and you have the polymer photogravure process.

One frustrating thing about alternative photography processes is the lack sometimes of critical information - such as the manufacturer's model number for a Toyobo plate when bought through a reseller. Toyobo makes many different types of plates for different uses. Note that none of the plates were developed specifically for photogravure. The best suited seems to be the Printight KM 73. A similar plate that can be used is the KM 43 - which has a thinner polymer film. A problem will arise if you start mixing plates up as the thicker the polymer, the longer the exposure required. Jon Lybrook suggests that the thicker plate allows for a deeper etch to hold more ink, giving richer blacks.

The plate has a clear protective film on the polymer which is removed prior to use. The unexposed plate shown above has a golden sheen. I'll talk more about preparing the plate later, but I want to note that I dust the plate with talcum powder which is mostly brushed off. The powder helps to eliminate air bubbles when you place the image emulsion side down on the photopolymer surface.

The plate is exposed in two steps: first with the image, and then with the aquatint screen.

The plate to the left was exposed for 1 minute 30 seconds with the positive image. Note the appearance of some detail as the polymer changes color when cured by the UV light.

The plate was then exposed with the aquatint screen after redusting with talcum powder.

The plate is washed by brushing with a soft broad brush in water for two minutes, dried first with some blue lint-free shop towels, and then dried completely with a hair dryer on high heat.

This photopolymer process is also called non-toxic etching or non-toxic photoengraving. No chemicals are used to etch the plate - water is used to dissolve the unexposed polymer. This is a very safe process compared to traditional copper plate etching. 

Once the plate is thoroughly dry, it is placed under the UV light source to fully cure the remaining polymer. The resulting plate is remarkably strong. In industrial applications these plates can easily print to the tens of thousands of images.

The final plate will look similar to the plate to the right.

While pretty rugged when cured, the plates should not be cleaned with water or alcohol which can damage them. Use low odor mineral spirits and baby oil instead.

On a humorous note, I would like to point out that the plate is reversed from where it should be. This plate prints out mirrored. A little mistake.

The plate texture looks very fine - Mark Nelson describes the surface as silvery.

The plate can hold a surprising amount of detail. The real question seems to be whether the process can produce images as detailed as that obtained from the traditional copper plate method. The consensus seems to be no - but the technology of polymer plates advances on.

Here is an enlargement of small text on the exposed plate. The numerals are highlights - raised relative to the darker (washed out during cleaning) background. The random pattern from the aquatint screen can be clearly seen in the area surrounding the numerals - providing the texture necessary to hold the ink in the black areas for printing.

I wanted to post some initial notes on the process. Jon Lybrook's notes are comprehensive and gave me a great head start on the entire process. 

In future installments I'll go into more detail on plate preparation, problems and solutions.

And eventually I'll return to the cyanotype discussion. Did I mention we entered the rainy season here in California? This threw a wrench into my plans for describing how to expose cyanotypes using the sun as a UV source. I suppose it just emphasizes that if you get very far into some of these processes, you will likely be unable to avoid purchasing a UV lightbox.