Earlier on I posted a few examples of the work I did in the final semester of my bachelors, Colour Photogravure from three plates. Well, these posts really asked more questions that they answered, and given that I may not get to revisit the process for a while I thought I’d post what I can.
These are the books I found useful over the course of the project. Some are more useful than others of course, but all of them are worth having on hand. I have a horrible habit of not being satisfied with having a library copy of a book because then I can’t make notes in the margins, which is why I buy them on Abebooks.
Dye Transfer Made Easy, by Mindy Beede
Clearly this is a book on Dye Transfer, but the section on making Colour separations direct from 35mm Colour slides is really well illustrated and explained. The DIY pin registration system they outline could also be of use. A lot of Dye Transfer literature could be applicable to certain parts of this process, so keep that in mind.
The Color Print Book: A Survey of Contemporary Color Photographic Print Making Methods for the Creative Photographer, by Arnold Gassan
Not tremendously useful technically, but very very interesting and handy to lend context to the work you’re doing.
Photogravure: An Archaeological Research, by Jan Pettersson
This is your key text. Pettersson deals with Copperplate Photogravure in his colour photogravure work, but most aspects are easily transferable to photopolymer materials if you’re not set up for copper. As far as I know this is the only contemporary work published on Colour Photogravure. See here for ordering details.
Toyobo Printight 73GR (thin) This is your photopolymer plate material. The Toyobo stuff gave me the best tonal range of all of the materials I tried, and it seems to be widely recommended for this purpose. (Available from Melbourne Etching Supplies)
You’ll need a Cyan, a yellow, and a Magenta etching ink. These are sometimes called Process colours as a carryover from the printing industry. Caligo make a wonderful range of water-washup process colours which worked absolutely perfectly for me.
Process Cyan (BL 24911)
Process Magenta (RD 63601)
Process Yellow (YL 91779)
They’re available in Australia from Neil Wallace.
This is of course vital. I use Magnani because it’s what I learned printmaking with, but nearly any etching paper will be appropriate to begin your experimentation with. Magnani Australia distribute a wonderful range.
If you’re making colour separations manually, either in camera or in the darkroom, you’ll need a set of colour separation filters to do the deed. Kodak made these in their Wratten filter line, but everything indicates that they’re no long manufactured. eBay is your best bet.
I used the following filters:
Wratten #25 – Red
Wratten #47 – Blue (Alternatively, 47b)
Wratten #58 – Green
Handy things to have
A Kodak Colour Separation Guide and Greyscale (Product code #Q-13). These are available from Freestyle Photo, and it’s endlessly helpful as a test target.
An Illumitrans Slide Copier, if you can get access to one, is really handy to have for making colour separations directly from slides onto black and white film.
A densitometer is necessary if you plan to get serious about this and get really accurate colours. I never had the chance to use mine appropriately.
You’re going to need an etching press, and preferably an etching studio.
I was lucky enough to have access to the South Australian School of Art’s rather lovely print studios.
You’ll need an ultraviolet exposure unit, and preferably a calibrated one. By this I mean, the unit measures the UV output of the bulb and adjusts the exposure time accordingly, so you know # units of exposure always equals # units of exposure. Bulb warm up and cooldown can be a real problem. Again, I was lucky enough to get to use the Photography department’s very nice exposure unit.
You’ll need to know how to print. If you’re coming to this medium without any print experience I recommend you have a printmaking instruct you on the proper methods. Paper handling, inking and printing procedures are really things you need to learn to do properly to avoid harming yourself or your equipment. The instruction of an accomplished printmaker is invaluable, as these are all things that are quite difficult to learn from books alone.
A brisk rundown of the printing process.
First, you make your colour separations. You then output these separations onto a transparent material, either digitally onto a medium like Pictorico, or in the darkroom by enlarging your separation negatives onto Ortho-Litho film. I used Arista Ortho film, which quite annoyingly has now been discontinued.
From these transparencies we make our plates. This involves contact the transparency onto the plate material under pressure, such as from heavy glass or a vacuum frame, and then exposing to UV light. How much UV light is up to a lot of testing, but since everybody’s setup differs it’s useless for me to tell you what my exposures were. “Enough” is about as much as you can say.
You also expose an aquatint screen in contact with your plate in order to give it the grain to hold your ink.
The plates are then developed and hardened as per normal. Photopolymer material is usually simply developed in warm water, which is quite handy.
So, we have our plates! Then we have to ink the plates up. You’re gonna want a big box of disposable gloves for this part. I found cheap plastic palette knives to be really useful for inking up my plates, and I used them more than the specially designed ink wipers I purchased for the job. Figures.
Ink up all 3 plates at once, and don’t dilly-dally, as you don’t want the ink to begin to dry on your plates. How much time this takes depends on the ink you use, but so long as you dont step out for lunch half way through you should be fine.
At the end of this inking process you’ll have your separate plates sitting all nicely lined up and ready to print.
Now, the printing.
Layer one, our yellow plate. Looks pretty boring.
On goes the Magenta! And it looks like…uhh. Orange. Hey, did we do this right?
On goes our Cyan, and it all comes together. It’s like this every time, everything looks pretty rubbish until you get to the Cyan layer and then things just click.
It’s worth mentioning that the printing order always goes Yellow, Magenta and Cyan. I tried printing in different combinations for kicks, and while you do get some interesting results they’re always muddy in comparison. So, keep this in mind.
That’s the basic rundown. I only had 6 months to explore this, so there’s lots more to be done, but I hope this makes you curious enough to explore further. I’ll post more when I can.