These are very interesting results, and I would add just one thing: if you use the bleach from B&W reversal processing after first development, chances are high, that you can indeed rebleach&redevelop color slide film as often as needed.
These are very interesting results, and I would add just one thing: if you use the bleach from B&W reversal processing after first development, chances are high, that you can indeed rebleach&redevelop color slide film as often as needed.
1) First dev.: Rodinal 1+50 or equivalent, approximately 9min at 20C.
2) Fix(non-hardening)
3) Bleach. Not blix and without formaldehyde or other chemicals that destroy the dye couplers. I used potassium ferricyanide+potassium bromide and a phosphate buffer, but ferric sodium or ammonium EDTA bleach will probably work fine too.
4) Re-exposure
5) Color dev
There is Alan Johnson's special B&W reversal bleach based on Copper Sulfate and Sodium Chloride, which together with an Ammonia clearing bath should do the trick. This bleach is much milder than one based on permanganate or dichromate.
This, however, will produce a negative image. The fix step removes the unexposed halide you need to produce a positive dye image.
As was suggested in another post, a copper sulfate/chloride donor bleach with ammonium hydroxide clearing bath will remove the negative silver image and allow looping for a positive dye image.
I've also found just sulfate+chloride bleach, will that work?
I don't know any reason it wouldn't. The key is that sulfate in solution reacts with silver, which then converts to insoluble silver chloride -- and ammonium hydroxide solution will dissolve silver chloride by not (readily) the other silver halides commonly found in film.
Copper sulfate is easy to source, BTW -- it's sold as root killer for use in drains.
Don't forget Sod. bisulfAte as a substitute for sulfuric acid. Used as a pH lowering agent for pools.You're right about nitric acid being probably the difficult one to get. Funny thing; I once bought it in rather concentrated form (I think 20-30%) as a pH reducer for horticulture, specifically hydroponics. I severely doubt if the shop in question was legally allowed to sell it, let alone to consumers. I also doubt they were aware of this issue.
Here in Europe, drain opener is usually sodium hydroxide. I read years ago that it could also be H2SO4, and I scanned all drain openers I came by in stores. It never was. I had to resort to battery acid for this - which is of course an excellent source; it's a known concentration and (as of yet) omnipresent. It's amazing what useful stuff you can actually find in shops if you actually read the labels!
Not really ambiguous. The amounts of developing agents I listed are guestimated on how much ЦПВ-1/CD-1 is used in a color dev. That is 1.15g for 0.5l. Bigger amount of developing agents is used because of their lower dye-formation activity. Then Ph-the optimal Ph for color dev. is 10, but here you have
A)more developing agent
and
B) 4-aminophenol, that is more of a BW developing agent, that is probably why at lower Ph I observed better dye formation.
Again, everything I listed, I would use as a starting point. The process most likely needs to be tweaked, and how it should be tweaked can only be determined after looking at the results. I would be very grateful for your tests as I currently don't have raw PPD
You should exclude hydroxylamine, since it acts as a bw developer and lowers dye yield.This is the simplified C41 recipe that I use, I find it the best recipe (in my opinion) as it is simple and the results are very consistent and very good.
This is the starting point for me.
You should tell me
What should I add to or exclude from that formula, so that I can follow your method?
This is what I understand..
I want this recipe to be the logical starting point and the beginning of the beginning.
Please modify this formula to suit your experience. Then you write the modified formula for you (according to your vision) by adding the other elements (PPD) and (4-aminophenol)
And I will prepare your recipe and make tests according to your suggested recipe. View attachment 310955
hydroxylamine, since it acts as a bw developer and lowers dye yield
The latter could very well be true, the former is apparently more if a theoretical issue than a realistic one. At one point I exchanged some PM's with PE and he said that the activity of HAS as a developer could probably be ignored in a color developer. Maybe it does interfere in another way, though.
You should exclude hydroxylamine, since it acts as a bw developer and lowers dye yield.
The recipe is
Potassium carbonate- 32g
Sodium sulfite- 1g
Potassium bromide- 1.5g
PPD- 6g
4-aminophenol- 3g
Water, bring up to 1L
You will need several color re developments to get a good density, so the first, black and white development is very important. What b&w developers do you have or can prepare?
You should exclude hydroxylamine, since it acts as a bw developer and lowers dye yield.
The recipe is
Potassium carbonate- 32g
Sodium sulfite- 1g
Potassium bromide- 1.5g
PPD- 6g
4-aminophenol- 3g
Water, bring up to 1L
You will need several color re developments to get a good density, so the first, black and white development is very important. What b&w developers do you have or can prepare?
I am sorry, got you mixed up with Athiril![]()
There is Alan Johnson's special B&W reversal bleach based on Copper Sulfate and Sodium Chloride, which together with an Ammonia clearing bath should do the trick. This bleach is much milder than one based on permanganate or dichromate.
The recipe is
Potassium carbonate- 32g
Sodium sulfite- 1g
Potassium bromide- 1.5g
PPD- 6g
4-aminophenol- 3g
Water, bring up to 1L
Without adequate sulphite in the mix, isn't PPD unstable in water?
Black and white developers available to me. They (Rodinal, Kalogen)
I can use either of them. I am waiting for your advice on choosing the developer that you created to comply with this process.
I think there are some things I got confused.
Allow me to ask some questions.
1- this process ,,
2- The films available to me are Kodak Gold only, will this work in that process?
3- Will this process produce a positive slide (E6), or will a negative film be produced?
4- Can this process be used instead of (C41) to develop Kodak Gold films to produce normal color negatives?
5-Is it necessary to use the re-exposure step?
6- Will we have to use separate Bleach and Fixer separate or can I use Blix?
7-I do not have ferricyanide bleach and will not have it available at the moment for financial reasons. I only have the great copper bleach, will it do the trick? .
finally ,,,
8- I hope you write me the steps, temperatures and times accurately.
Thank you God bless you
I will not agree to the use of (Ammonia clearing bath) I have used it before and the smell was very strong and harsh and I felt some suffocation and almost passed out,,
Can ammonium per sulfate bleach be used? directly
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