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B&W Reversal using a Chromogenic Process?

ChrisGalway

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Has anyone tried B&W reversal processing using a chromogenic (black) dye process?

Might it offer any advantages (reduced grain?) or disadvantages? I note that Ilford XP2 for example uses a chromogenic process ... but it's a negative, not positive, process.
 
For some reason they come out with a strong magenta tint...
 
XP2 Super is easy to reverse.

First, develop in any convenient B&W developer with a very little thiosulfate or thiocyanate added (this can be adjusted to get the final density you want).
Second, expose the film to light (still on the reel generally works) -- and give it lots of light, to be sure it's completely fogged.
Then run through a standard C-41 process. Result: slightly pink B&W slides. Shoot tests to get the correct EI, first developer fixing level, and first developer time.
 

Thanks for this info ...

I confess when I asked the original question I was thinking more in terms of any normal B&W film, and a reversal process analogous to Kodachrome but involving only one black dye. One of the problems of reversal processing is getting a good dark black and I thought that a dye might give an improved result.

But thanks again.
 
If you could obtain a "black" dye coupler, that would work -- dye couplers from a color toning kit (combined with C-41 or RA-4 color developer) could do the job, but the color toners only come in single color, and mixing the toners would dilute the couplers and give a gray (it might be okay combined with retained silver, or it might not). But color toners for B&W prints aren't easy to find any more, either.
 
ChrisGalway said:
One of the problems of reversal processing is getting a good dark black
Click to expand...

Why do you think so? I can undertsand if DIY reversal didn't produce great results as it is very operator dependent but has anyone complained about either Scala process or Dr5 not producing a good dark black?

ChrisGalway said:
I was thinking more in terms of any normal B&W film, and a reversal process analogous to Kodachrome but involving only one black dye.
Click to expand...

I would be interested in seeing your results if you take this route. IIRC @Ian Grant has posted useful info on dye couplers which might be helpful to you.
 
You can run XP-2 through E-6.
 
Raghu Kuvempunagar said:
Why do you think so? I can undertsand if DIY reversal didn't produce great results as it is very operator dependent but has anyone complained about either Scala process or Dr5 not producing a good dark black?
Click to expand...

I've reversal processed Rollei Superpan 200 using the Scala kit. The results are quite nice but the blacks could be darker. (I use 120 size, and the Scala 50 film is not available in that size.)

As for Dr5, everyone says it was excellent, but the processing procedure still appears to be secret. (Is there any update on this I wonder?). Because it is said to work so well on all films, not just high silver content films, perhaps it uses a chromogenic process?
 
ChrisGalway said:
I never thought of that! Have you (or anyone else) tried that? Any tips to suggest?
Click to expand...

Not with XP2, but I have tried with a few old rolls of Kodak T400CN, and it worked. I had to over expose (not sure if this is just negative to positive or the fact the the film was 20 years old.) The result was very green. I'd be curious if XP2 is also green, or some other color.
 

It's unlikely that Dr5 used any such thing. You can always use Chromium intensification to add imagewise density to the slide if the blacks are not dark enough.
 
I have been researching this idea from the point of view of diffusion transfer printing (and wondering whether there is a dye-developer that gives a black image). Things I have read suggest that nobody has ever found the holy grail of a real black dye coupler. Does anyone know different?
 
while I haven’t tried it with xp2 (yet) m, ilford Pan F+ 1st developed in d-67 (sixty seven!) then stopped, bleached, cleared and redeveloped in Kodak FD-72 (fogging developer, NO relation to D-72) gives excellent blacks and very clear highlights. IE for me is 25 with this arrangement. If you can find Fomapan R, this also works well with the same arrangement, very deep blacks and EI (for me) of 80. I have tried the D-67/FD-72 combo with a bunch of films and the best results come from PanF and Fomapan-R. I have had fair results with HP5+, Rollei Superpan (EI 160) and Rollei RPX (EI 25). Most other films did not reverse well for me in this combo (Trix, TMAX 100 & 400) Delta 100 &400, Fomapan 100, Fuji Acros, FP4+}. I would send some examples but everything is packed up for a household move so will have to wait.

FD72 uses sodium metabolite, cysteine HCl & sodium dithionite. It must be used FRESH every time, no mixing and keeping it around a few hours or days. If it is not fresh, blacks are washed out.

Kodak fogging developer FD-72

Part - A
EASTMAN Sodium Dithionite: 5.0 grams

Part - B
Water: 900 ml
KODAK 'Kodalk' Balanced Alkali or sodium metaborate tetrahydrate: 10.0 grams
EASTMAN L-(+)Cysteine Hydrochloride: 0.3 gram
Add water to make 1 litre

Use: Dissolve 5 grams of Part A in 1 litre of Part B just before use - it only has a life of about 2 hours after mixing.

Here’s D-67 in use mine replenished.

Kodak D-67
Warm Water ( ~50ºC )
500 ml

add and dissolve
Kodak Elon ( P-Methylaminophenol Sulfate )
2.0 grams
Sodium Sulfite ( Anhydrous )
90.0 grams
Hydroquinone
8.0 grams
Sodium Carbonate (Monohydrated)
52.5 grams
Potassium Bromide ( Anhydrous )
5.0 grams
Sodium Thiocyanate
1.5 grams

then add
Cold Water to make 1 L
 
Kodak in J-6 pamphlet says:

" Keep the volume of the first developer solution constant by adding KODAK Replenisher D-67R. The activity of this replenisher is based on an average carry-over of about 5 fluidrams (about 18.5 ml) of solution per 36-exposure roll (approximately 5 feet processed). To prevent an increase in developer activity, replace any loss of first developer greater than this quantity per roll with first developer solution (KODAK Developer D-67). If the volume of solution lost is less than 5 fluidrams (18.5 ml) per roll, remove sufficient solution to permit adding the correct volume of replenisher."

D67R formula:

KODAK REPLENISHER D-67R FOR USE WITH KODAK DEVELOPER D-67​

Ingridients Metric
Water about 125°F (50°C)
KODAK ELON Developing Agent 2.0 grams
KODAK Sodium Sulfite (Desiccated) 90.0 grams
KODAK Hydroquinone 8.0 grams
KODAK Sodium Carbonate (Monohydrated) 52.5 grams
KODAK Sodium Thiocyanate (Liquid) 7.5 ml
Water to make 1.0 liter


Have you ever experienced a yellowish or sepia tone on slides when using FD-72 as the second (fogging/reversal) developer?
 
I used to use XP2 to make black and white negatives directly from colour negatives. The negatives provided by the client were for press kits, and black and white prints were required.

I used to expose the XP2 film, and then process in our E-6 line, to produce a negative in one step. The initial tests produced a very flat negative, so I would “push” the film 4 stops.
 
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