Bad HAS?

[Photo Engineer]

Each CD varies in the hues of the dyes they produce, the contrast of the individual images, and the stability of the dyes produced. In addition, they each vary in their contact dermatitis and other toxicity issues with humans. That is one reason why CD3, CD4 and CD6 are in the final select set of CDs for color processing. They optimize the best of these qualities for the films with which they are used.

PE

 

[Quiver2]

So how badly has this affected the dye stability of the developed negatives? I'm taking a guess that this unintentional cross processing hasn't done great things for it, but how bad is it?

 

[Photo Engineer]

CD1 and CD2 were notorious for bad image stability compared to the others, and were no longer even tested in our labs against modern couplers. So, I could not even begin to guess. But again, we have no assurance that this is indeed one of these two. It could be something else entirely.

PE

 

[koraks]

On a side note, do you have a pH meter? Last night I mixed moth C-27 and C-29 according to the formulas posted here and in both cases the pH seems rather high (around 0.25 too high) and test strips seemed overdeveloped and showed very poor saturation and color crossover. Neither of my cheap pH meters is necessarily reliable, but I can tell that the pH is quite far off the mark. I ran some strips with adjusted pH, but I still have to make some test prints; contrast does seem better judging by the negatives.

 

[Quiver2]

If you're using tap water this could be a source of variation. After making to 1 liter my pH meter showed 10.15. Then again I was using sodium carbonate which could also make a difference.

It would probably be best to assume that it is CD2 and figure poor dye stability then. Though as you said there is no assurance that this is CD2. Having a mystery chemical in my inventory is not calculated to give me warm fuzzy feelings. A query: Would a change of mixing order be required if CD4 was not in the form of an acidified salt?

 

[koraks]

If you're using tap water this could be a source of variation.

Not that much. I used anhydrous potassium carbonate; maybe I'll run a test with sodium carbonate. Your 10.15 is exactly on the mark; sounds good!

 

[Anon Ymous]

On a side note, do you have a pH meter? Last night I mixed moth C-27 and C-29 according to the formulas posted here and in both cases the pH seems rather high (around 0.25 too high) and test strips seemed overdeveloped and showed very poor saturation and color crossover. Neither of my cheap pH meters is necessarily reliable, but I can tell that the pH is quite far off the mark. I ran some strips with adjusted pH, but I still have to make some test prints; contrast does seem better judging by the negatives.

I haven't tried C27 yet, but I've tried C29. Like you, I noticed high pH, about 10,3 in my case. Adjusting it to about 10,17 gave me reasonably good balance, with the RGB channels having fairly parallel curves. Without this adjustment, the negatives looked ok, but there were significant colour casts, that wouldn't be correctable in RA4 printing I suppose.

 

[Quiver2]

Just started scanning negatives, and have a few things happening here that I'm attributing to having a mystery color developer compound. The negative mask was more orange than what the scanning software was expecting. It showed up as if the software wasn't compensating for the mask. This was able to be corrected with an adjusted white balance. I realize that this isn't the hybrid forum, but this seems like something that should be mentioned. The other thing is that while I only overexposed by one stop when I was taking these photos there seemed to be a significant apparent speed increase. The only other speed increasing developer that I found for C41 was mentioned in this thread: https://www.photrio.com/forum/threads/why-is-there-color-crossover-in-divided-c-41.99982/page-2 = This developer also used CD2. I think that CD2 may have a speed increasing effect in the development of C41 films.

 

[Photo Engineer]

CD2 is quite active, but IDK relative to CD4. I tested CD2 against CD3 and the former is very much more active than the latter. CD4 is more active than CD3, but I don't know how this relates to CD2 vs CD4.

PE