Recent content by IB Photochemistry

I have never tried to separate Kodachrome film myself. From what I have heard its more difficult to separate than chromogenic films. The E-80 manual recommends one use the green principle mask on the red separation negative. This has the effect of removing cyan from the magenta. Remember...

One can argue the about the skill in assembling a final DT print, and there is some craft to that. I have done (and still practice) it fairly well myself. Without good separation negatives it is nearly impossible to make a high quality print. The rinse controls effect density and highlight...

I completely understand how the use of an extinction filter dye will produce an exposure modulated relief image. I can say with certainty it was NOT unhardened Super XX pan. I have measured sensitivity at 700 nm, which as you might know Super XX really has no good sensitivity there. I couldn't...

To respond to koraks on my use of the term “internal masking” or “masking” of chromogenic materials, I probably should have used the terms Interimage Effects, so as to avoid confusion. Interimage Effects occur in chromogenic materials but most of that is beyond the scope of this thread. They act...

He probably used a shadow contrast increase mask with the separations, either as a “black” mask made to be exposed in contact with the pan masking film and separation negative for the CRM, or off an intermediate interpositive. I believe he was using Separation Negative films.

Gord, have you used any of the methods for making photographic separation negatives I posted here? I hope they can be helpful to people interested in this approach. Its good to hear someone else interested in making DT prints on here.

No, Lachlan you have the misunderstanding. All chromogenic color materials, E6 films, RA-4 papers, and color reversal papers, have internal color masking for correction of their OWN DYES. Lachlan is making a muddle of the dyes used in the NEGATIVE FILM and the DYES USED IN THE PAPER. I think we...

But he didn't make the type of highlight masks typically used in DT. In fact he made some rather disparaging remarks against me saying “imagined and historically incorrect “, to the kinds of masks I discovered in my research, and which I can document, were being used in the industry. In my view...

I think what I said was you made at least one set of separations for DT but didn't make highlight masks. You then seemed to agree with me that you didn't make highlight masks, but that I was “twisting my [your] words”, then you went on about that you thought it wasn't necessary. I don't know if...

I will soon post some examples of some Dye Transfer prints I rolled myself, some of my equipment used, and separation negatives, and masks.

These forum members saying this never worked in a commercial DT lab that I'm aware of. There are a few people on Photrio who I know of that have done this commercially, but haven't commented on this thread either way.

Bob, I am currently actually MAKING DYE TRANSFER PRINTS now, unlike Drew and Lachlan. I made some transfers last year and would like to make another in the next month or two. What kind of examples do you want to see? I have pictures of masks and separation negatives, curves, etc. I used all of...

I can't locate the source I used, so I'm not sure which film was 26 stops of range. Cine films can have more than 21 stops. Portra NC160 has 23.9 stops of dynamic range according to Frédéric Cao in a publication. Portra 400 can have at least 19 useable stops, and there are people who have over...

My goal is to support interest in this type of process in the fine art industry. I don't have enough old stock Kodak matrix film and paper to do this commercially. This is only a very small part of my research into DT. Color separation methods are also of use to other processes. The fact is Dye...

No, not any general purpose film will work well for continuous tone separations. For separations of color transparencies each of the three narrow-band spectral exposures needs to be recorded on film as linearly proportional to the dye curves of the transparency. This requires proper spectral...