U of S | Mailing List Archive | alt-photo-process-l | Re: Anyone doing autochrome?

Re: Anyone doing autochrome?



Barry,
I had the joy of being in the bromoil class with a chemist physician who practiced whatever that field of medicine is where they determine risk and safety stuff at large corps. Anyway, he was a wealth of photo lore. One thing he told me was that the slime goop that kids play with is none other than gum arabic (or even PVA in some cases) mixed with boric acid. Boric acid makes gum go instantly hard (gum viagra?). Jim suggested using this as a sizing. Coat the paper with gum and then harden it in a 1-2% boric acid bath. As a person offlist reminded me, though, when I added acids to my gum mix I got more and more staining/non-exposure hardening in my gum layer as per the example on my website in the learning section on gum, so it may be an iffy proposition. I wonder if the residual boric acid would then affect subsequent gum layers, making it unsuitable for gum, but certainly this was a less toxic form of sizing to dink around with.

But ANYWAY, is it possible to do some sort of boric acid/gum thing with your class and allow them to make goo to play with? What is it called, GAK?

Then, this guy also did a copper sulfate print which was really quite beautiful, reminiscent of Bernie Bertridge's cupric print at APIS. I think it might have been Obernetter's formula, or something he devised himself. So that could be done in tandem with a cyanotype demo--a pink print and a blue print. And copper sulfate is cheap. If you want, I could email him and ask his formula.
Chris



----- Original Message ----- From: "Barry Kleider" <bkleider@sihope.com>
To: <rvallon@cox.net>; <alt-photo-process-l@usask.ca>
Sent: Wednesday, August 29, 2007 7:52 AM
Subject: Re: Anyone doing autochrome?


Hi, Richard,

Thanks for writing.

I've seen enough autochromes to know what I'm looking at, but I can't say know much about the autochrome process -- except that it produces a color image using potato grains on a B&W base emulsion. I know the originals were done on glass plates. I accept that we don't have a multi-ton press in a light-tight room to make the real thing. Even if the images were a bit fuzzy, less than permanent, could the process be done on B&W sheet film?


My interest in asking is that I work with high-school students in an arts-infused program. This means we use the arts to teach other ubjects -- chemistry in this case. For the past two years I've been doing cyanotype printing with a group of chemistry students as a way of teaching about chemical reactions. I'm hoping to deepen my bag of tricks as it were. So, I'm not looking for a digital rendition, but an actual physical/chemical process. (In the best of all possible worlds, I could wow my students by showing them photos made from a potato.)

BTW, the idea of doing autochromes was only one thought. I'd entertain any other ideas for other darkroom chemistry projects. Keep in mind these are high school students. Anything involving critical measurement of hazardous chemicals probably wouldn't look too great on the evening news.


Barry




Richard Vallon Jr. wrote:
On Aug 28, 2007, at 1:58 PM, Barry Kleider wrote:
Is there anyone on the list with experience doing autochrome printing?

I'd like to do some experiments on my own and then offer it to some of my high school students.

Barry Kleider



Hi Barry-

Are you familiar with this process? I'm asking as it is a glass plate covered with colored potato starch grains.
The grains are pressed together under a multi ton press then the back of these grains is coated with a photo emulsion
- this plate is then developed as a positive after it has been exposed in camera...
The final result is a color transparency...
So the chances of anyone doing this themself w/o a research grant are small.

However- it would not be impossible to contact print onto color photo paper through a multi colored screen made in an inkjet printer.
I also have a simple digital method in photoshop that looks very similar to an autochrome.
If this interests anyone I can write this up...


Richard Vallon - Orleans Photo Inc.