Recreating Autochrome

[Aurum]

Reading the Thread started in Colour Darkroom, got me thinking about this process again

http://www.apug.org/forums/forum40/5...lop-these.html


Reading back through this thread below started by htmlguru4242, it seems that from time to time this has been considered in depth, but I think its fair to say that it has never seemed to really get going in the way that those involved would like

http://www.apug.org/forums/forum42/1...tochromes.html

Now a few years have passed since then, and I think digital printer technology has improved somewhat, so that got me thinking about ways to recreate the old fashioned look of this process, but possibly with a hybrid / alt process.

Now I've been trying out gum Bichromate printing for a while, but instead of using normal sized negs (35mm, 6x6 or 6x9) or creating sheet film internegs using an enlarger, I ended up doing a hybrid process of taking a scan, or original digital photo, preparing an A4 sized negative in Photoshop, then printing the neg out in work on one of the laser printers dotted around the office onto heat resistant acetate.
It may offend the purists, but it works well, and the negs are dirt cheap to replace if I wreck them.

But I digress here

A typical HP laser colour printer like I can lay my hands on at work has a typical colour resolution of 600x600DPI, and I suspect that the newer photocopiers we're hiring go higher than that. They print nicely onto acetate, and the dyes used are waterproof, but I haven't tried them with caustic or acidic solutions.

I'm thinking here that if I print a random coloured mask onto one side of the acetate, or a copy of the dot pattern on a color CRT this may be fine enough to act as the filter in an autochrome sort of fashion. (or a hybrid autochrome/Dufaycolor thing)
If I then coat the reverse side of the acetate with paintable silver emulsion in a pot, provided it sticks, it should give a home-made version of a LF sheet film

Question: Of the commercially available amateur products, which would be considered a good bet for a fast emulsion? I ideally would like something that is going to expose quicker than regular printing out paper, and even better something that will stick like the proverbial to a blanket to plastic sheet.

The other idea, is one that was touched on in the previous thread on this subject.

This is pure conjecture from this point so if anyone can tell me why I'm talking Bovine excreta, I'm all ears to save me going to the trouble of reinventing a wobbly square wheel

I'm a cosmetics developer, so that means I have access to a different pallette of materials to other chemists, especially when it comes to powders, pigments and pearls. I've located polyethylene powder in 16-22 micron size (Uncoloured unfortunately) but it should be available in other colours. This could in theory be used as a starch grain replacement either direct, as per the original process or coated onto a glass substrate, and fired in the oven (Polyethylene typically melts below about 120 deg C) Nylon might be another idea, but I need to go digging on this.

Still first things first, I'll see if the acetate sheets can give a decent shadowmask first.

[Martin Reed]

Originally Posted by Aurum

....
Question: Of the commercially available amateur products, which would be considered a good bet for a fast emulsion? I ideally would like something that is going to expose quicker than regular printing out paper, and even better something that will stick like the proverbial to a blanket to plastic sheet.
....

Problem is, all the off-the-peg emulsions are blue sensitive & slow. If you were to do anything along these lines you need the co-operation of a commercial manufacturer who can supply fast panchro. emulsions.

After Autochrome there were a number of other more 'sophisticated' screen plate based colour systems before Kodachrome came along, and these are hardly ever mentioned, let alone researched. If you're talking about using contemporary inkjet methods of laying down dyes these might be the ones to look at. The problem? They didn't have the charm & built in artistry of Autochrome.

[Photo Engineer]

What you are describing is technically more like Dufay color film, not Autochrome. And, yes it can be done. I posted earlier that I had seen it done at George Eastman House.

Basically the color screen was printed on a sheet of acetate and then the material was placed over a sheet of commercial film and the sandwich was exposed. After processing, the screen was again placed over the film in register and a color picture resulted.

As Martin says, the current liquid emulsions run about ISO 12 or less on film support and I know of none that is panchromatic. That isn't to say that one might not exist, but that will be your big problem. Well, that and the fact that if you do not use dyed particles it isn't Autochrome, it is something else.

PE

[Sean]

I'd have a look at hybridphoto.com your topic doesn't quite fit here. Thanks