Tmax 400 Film for Color Separations

[ciocc]

Thanks for the mention @relistan! I'm even more amateur than @ciocc, but I appreciate it. In any case, it seems the resident experts like @DREW WILEY have chimed in here, but he also shared this info on a tricolor thread here on Photrio:
https://www.photrio.com/forum/threads/color-images-from-b-w-film.174977/

Thanks for that post by Drew. He is correct. This is how it was done "back in the day" of Carbro and Dye Transfer. I'm suffering from nostalgia. Dye Transfer and Carbro is dead, but Carbon is within reach of amateurs like myself.

 

[DREW WILEY]

Dye transfer is quite alive, but on a restricted basis. A couple in Germany has a significant commercial DT lab based on materials custom made for them, as well as new specialized equipment. I have enough DT supplies on hand for about five years of printing, but at this point don't know where the find that particular window of time. I'm on a bit of a roll getting markedly improved chromogenic color printing results, as well as still bering highly active in traditional black and white printing. A decade or so ago it was estimated that maybe 200 people worldwide were still DT printing; now it might be at most half that number. Carbon printing and related pigment process supplies are easier to improvise than DT essentials. But anyone with enough will and serious money could hypothetically revive the paper and matrix film necessary to DT. During its heyday, there were at least five different manufacturers; Eastman Kodak wasn't the only game in town. The dyes themselves are easily acquired.

 

[ciocc]

For those that may be interested:

I wanted to verify the claim that Tmax 100 will develop RGB separations to the same contrast. I loaded up a roll of Tmax 100 into my 6x7 camera and took a pic of a "still life" under flash. I included a Kodak color separation guide and reflection grayscale. The reflection grayscale has indicators for highlight, midtone and shadow. I developed the roll in D76 for the time recommend in the datasheet at 20 degrees C. I measured the highlights, midtone and shadow density for each negative. Here are the results:

Highlight
------------
Red = 1.35
Green =1.40
Blue=1.42

Midtone
------------
Red = 0.93
Green = 0.97
Blue = 1.02

Shadow
-------------
Red = 0.28
Green = 0.34
Blue = 0.51

The blue filter negative is a little heavy in the shadow area, which means the yellow printer will be a little thin in the shadow areas relative to the other two printers. That's ok, because the highlights, where accurate rendition is important, is darn near spot on. Same with the midtone areas. I'm very excited. Now if I can get my CYM pigment papers reasonably balanced, I should get a decent color assembly print.