First Test

Yesterday I decided to spend a chunk of time and learn how the polymergravure plates work. This material is Toyobo Printight KM73 and it is a photosensitive layer of polymer bonded to a thin aluminum plate that is very flexible.

I have a 21-step Stouffer test wedge and used it for my tests. I cut on a large old paper-cutter (the guillotine kind...) 3 seperate 1x8 strips.

I'm using the Nu-Arc plateburner in the USU lab. It measures units of light rather than seconds of minutes. The 'Joule' is a standard that is used to measure output and intensity of light. One joule = ???? I don't know actually, it's just a way to measure and quantify light. Here's how the tests broke down:

Test #1 - 100 Joules on step wedge, 100 Joules on stochastic screen

The method used is as follows:

a. place plate face-up
b. place step-wedge emulsion side down
c. sandwich with pressure under glass
d. expose for (x) Joules of light
e. remove step-wege
f. place stochastic screen emulsion side down on top of plate
g. sandwich with pressure under glass
h. expose for an equal amount as was done in step d
i. remove plate and process

Here is an image of the plate-burner with my plate sandwiched in my home-made contact printing frame.



After you have exposed the plate, you need to develop it in running tap water that is cool to the touch. Boxcar Press has a very good datasheet on the exact way to process the KM73 plate. You can download it from their site HERE.

One thing it DOESN'T mention is that you have to peel and remove a thin layer of protective film that is clear and kind of hard to see. I saw it and thought it was the actual polymer itself and was afraid of removing it, so I didn't.

I developed my first test strip with the protective plastic still on it. No image developed because no water was reaching the polymer. DOH! While it was developing under the running water, I thought I needed to make my exposure time longer so that I would get a good exposure on the plate. So, I started my next exposure while test #1 was still developing.

Here's how I did test #2.

500 Joules on step wedge, 500 Joules on stochastic screen

While the exposure for the screen was happening, I discovered that I needed to remove the film. A quick call to Boxcar and a chat with Nancy (?) and I realized I'd made a significant blunder.

I got back into the studio from lunch and removed the plastic film, and developed test #1. I did get a faint image that took on more relief as the plate dried and cured.

Since test #2 had already been exposed I decided to go ahead and process it also. I removed the film and processed it, getting slightly more relief on the plate.

If a little more exposure is good, then a lot more exposure would be better right? I cranked up the exposure unit to 999 Joules (it can't go any higher) and exposed the plate for test #3.

999 Joules on step wedge, 999 Joules on stochastic screen

I processed it and the relief is quite deep. Deep enough that I felt good about showing it around. Several who saw it thought it would work well to run through the press as a test, so I thought I would.

I got some BFK Rives and tore it down into small strips. I soaked them for about 20 minutes while I prepared the rest of the stuff I'd need.



Cole and one of the undergrad students (whose name ex-capes me right now) helped remind me how to prepare a plate and run the press. I did some printmaking as an undergrad, but that was in '94 and I'd forgotten everything I thought I'd learned. Good thing that there are friends around to hold my hand and help me along.

I got the plate inked up and ran a test.



I was pretty excited that it even worked just a little. I can see the step wedge and gradations but there are some problems.

I am seeing an uneven wave in the dark areas of the print. As I have inspected it I am deciding that it is the result of a wave in the actual plate. The plate is made out of very thin aluminum (I think...it might be stainless...) and as I cut it I can see that there is a slight curved lip on the edge of the plate.

I am thinking that any unflatness in the plate can cause uneven contact with the negative, the screen or even the printing paper. I will have to figure out a better way to cut down the plates without getting any distortion of the metal.

I want to practice getting those bugs out a little bit more before I commit to start making my own digital negatives.

Here's the two proofs I pulled last night with the plate next to it.



I think I remembered why I love printmaking so much. Too bad I suck at it.

Procurement

So I've gotten my plates from BoxcarPress, picked up some Pictorico OHP from an undergrad student who was ditching a brand new box of 8.5x11 for $20 (a pretty good price considering I didn't have to pay $13 for shipping and no tax...), and now I'm ordering my aquatint screen from Dan Welden.

I have several good papers at home, I think they'll work well for the gravures. I'm considering using some special ink and trying a bunch of different papers later on, but first I just need to get the plate-making down.

The practitioners of the 'solar-plate' or 'polymer-gravure' use two different techniques on how to create the plate.

The first is to create the negative as a smooth continous grey-scale image, and then to double-expose the plate. You expose first with the aquatint screen (80% grey), then you remove the screen and expose with the negative (actually, a positive...).

The other idea is to print your negative digitally and have embedded in the image the actual random dot pattern or a 'dither' into your image. I tried this way two summers ago in Rexburg, printing out the digital negative as a bitmap file. Although the gravures that other students did looked pretty good, I knew it could be better.

I found Susan Voss' site and learned how she was doing the double-exposure tecnique and have decided to not even bother with the bitmap dither at all. My feeling is that you lose the gentle grey-scale-ness of the print, and that it ends up looking too 'digital'. With the Stochastic screen printing, the prints are more luminous, have a much more gentle greyscale transition, and look like the gravures I'm trying to emulate from the old masters (Curtis, Steichen, Steiglitz, etc...).

I saw a wonderful demonstration on solarplate at the Alternative Photography International Symposium in Santa Fe, New Mexico several years ago. I do remember the wash-it-in-water nature of his process, and the polymer-gravure name of the plates he was making. I think his name is David Hoptman...the workshop presentation/demo is listed in his CV.

I also remember how beautiful they looked, and it has stuck in my head all this time. Hopefully I can get a good start towards making some good prints. I know it can be done, it's just a matter of me learning how I can do it.

I need to get going on this because I'm quickly running out of time in the semester. Approx. 3-weeks left. EEEK!

Intent

This will be a repository for thoughts, experiments, tests, failures and successes in my pursuit of making photogravures from a polymer based gravure plate. Details to follow. Hopefully this will be a place where I can share what I learn and receive feedback from those who have trodden this path before me.

That's all for now.