Tr-Color Neg creation

[David Nash]

Hi

A few years ago I tried tri-colour gum printing, without much success! I'm now going to go back to basics, and thought I'd initially try scanning the negs into Photoshop etc before learning the intricacies of gum printing!

I have a Lee tri-colour filter set. I first of all need to work out the filter factor for each of the three colours. I'll then meter for the scene, then photograph the scene with each filter in turn, adding the appropriate filter factor for each colour.

If if this is correct so far, my main question concerns developing the negs. Can I process the three negs at the same time (ie with the same development time), or do each of them require different contrast?

I'll try this first, then I'll probably post a question about layering and colour subtracting (or whatever the term is) in Photoshop later!

Thanks

David

[Bill_1856]

I can't help you with the gum prints, but I stopped doing Dye Transfer 30 years ago and think that I still have a hair shirt in my closet which I could send you.

[David Nash]

Thanks, Bill. You're a gentleman! Please send it on the next clipper bound for Great Britain...

I couldn't sleep last night, and ended up reading an old photography manual (dated 1932!) where colour photography for everyone was just a pipe dream. However, it made me want to investigate for myself. There's just something about the idea of making a colour print from B&W negs that sounds almost unbelievable (I'm not a physicist!), and I'm keen to see it happen under my nose!

David

[Graeme Hird]

I'm interested in this process too, since I believe that I may be forced into doing my colour photography this way eventually (when the film makers stop making the film I like). Any answers you get here David will be stored away for later reference.

However, I don't think I'll need to get serious about the process for a few years yet.

My gut instinct says you should give all three films equal development and exposure (ie - don't change the contrast).

Cheers,
Graeme

[Larry Gebhardt]

My gut feeling is you will need to adjust the exposure because tmax isn't linear over all the colors. I would start with the same development and adjust contrast in photoshop if you need to. Use this as a guide for the next set's development.

Let us know how it turns out.

[CP Goerz]

The blue neg will need twice the development of the red and the green will need one third more. This was from a guy I chatted with who at the peak of his creative output with everything going perfectly could make two carbro prints a day.

CP Goerz

[Jim Galli]

Not a few times on Ebay and once in person, I've seen the beam splitting cameras that seperated the 3 colors and sent them to 3 planes and make all 3 negs at the same time. They aren't very expensive as there's only one guy left on earth that wants one. Saw one in Reno that was 5X7. Wouldn't that be the best place to start? When you get the hair shirt, make sure you wear it "hair in". This is punishment right?

[sanking]

Jim,

If you see another of these old tri-color cameras available in good condition at a decent price yell at me. I am another of those guys on earth who would like to have one of these, preferably a 5X7. I would really love to make some tri-color carbro prints using separations made with the equipment they used in the old days.

[Jim Rice]

So am I insane for wanting to make dye transfer prints?

[Jim Galli]

Jim, Only slightly more so than any other LF wacko. Contact me off line if you want a bunch of Agfa stuff that came with a large darkroom buyout. I don't know what the stuff is but it's something to do with dye transfer I'm sure. Would happily trade for a finished dye transfer print someday. Jim