Cinestill DF96 monobath

Donald Qualls · Aug 23, 2020

Preliminary results are: XP2 Super (metered at box speed) works just like TMax 400 in Df96 -- including needing double time to fully clear. I washed and gave a C-41 final rinse (I've been using that as wetting agent for B&W film, too), pulled the reel out of the tank (after 5:30 at 80 F, standard agitation, i.e. "Push +1/2" according to the chart) -- and the header and rebates were milky pink. Rinsed off the final rinse, and back into the Df96 for another 5:30, after which they look very much like normal negatives except for the pink base (which I gather is normal for XP2 Super even if processed in C-41 chemistry). They're drying now, but here's a phone snap of the hanging strip (the background shows through the negative, it's actually very normal looking). IIRC, this was f/8 at 1/100 but the overcast had enough holes that I'd get four stops light variation over a few seconds.

Raghu Kuvempunagar · Aug 23, 2020

Pink colour is normal. It doesn't go away with longer fixing. As long as you are happy with shadow details (which are hard to discern from the pic of the negative you shared), you seem to be doing fine with XP2 Super.

Donald Qualls · Aug 23, 2020

Raghu Kuvempunagar said:
Pink colour is normal. It doesn't go away with longer fixing. As long as you are happy with shadow details (which are hard to discern from the pic of the negative you shared), you seem to be doing fine with XP2 Super.

No, but the milky opacity does go away with extra fixing. When I first pulled the negatives out, I couldn't see through the rebates. After doubling the time, I could.

C-41 films are notoriously hard to fully fix, much like tabular grain (in fact, I think I recall that all or almost all modern C-41 films are tabular grain -- even with separate bleach and fix steps, it's a 6 minute fix in a rapid fixer). I almost pulled out my bottle of Kodak Rapid Fixer, but the Df96 was still in the graduate, already measured, and in the same temperature range as the wash water (for which I usually use the tempering bath with an Ilford wash).

I haven't yet scanned these negatives, nor examined them with magnification, but I surely know how to adjust my EI in case of inadequate shadows. For me, this is a test, almost a stunt, anyway -- I have C-41 chemistry on hand as well, and though it's also a little tired, I can be pretty confident I don't need to worry about color crossover or casts with XP2 Super.

Donald Qualls · Aug 23, 2020

Okay, i got the negatives scanned. There's something not quite perfect about the contrast; I'm not sure if it's a scanning problem that wouldn't show in a print, or if it's a previously unmentioned issue with processing XP2 Super in B&W (or if it's something specific to Df96). I won't be able to tell until I can print it, hopefully not long after Labor Day. Scans herewith:

Wirgin Auta 4.5, XP2 Super, EI 400, Df96 monobath.

Raghu Kuvempunagar · Aug 23, 2020

Donald Qualls said:
No, but the milky opacity does go away with extra fixing. When I first pulled the negatives out, I couldn't see through the rebates. After doubling the time, I could.
.

Milky cloud is due to insufficient fixing and surely additional fixing helps in this case. However, pink colour of the base doesn't go away with additional fixing.

Donald Qualls said:
pulled the reel out of the tank (after 5:30 at 80 F, standard agitation, i.e. "Push +1/2" according to the chart) -- and the header and rebates were milky pink.

Curious to know if you checked the film in complete darkness using night vision IR goggles. Wouldn't inspecting an insufficiently fixed film with lights on result in fogging when the film is put back in the monobath?

Raghu Kuvempunagar · Aug 24, 2020

Donald Qualls said:
C-41 films are notoriously hard to fully fix, much like tabular grain (in fact, I think I recall that all or almost all modern C-41 films are tabular grain -- even with separate bleach and fix steps, it's a 6 minute fix in a rapid fixer).

When you use C41 process for developing C41 film, the fixing step needs to remove both the bleached silver image as well as the unexposed/undeveloped residual halides. That's why fixing takes more time. However, when you develop XP2 Super in B&W chemistry, you want to retain the silver image and remove only the unexposed/undeveloped residual halides. Fixing in this case shouldn't take much longer than a regular B&W film.

Donald Qualls · Aug 24, 2020

Raghu Kuvempunagar said:
When you use C41 process for developing C41 film, the fixing step needs to remove both the bleached silver image as well as the unexposed/undeveloped residual halides. That's why fixing takes more time. However, when you develop XP2 Super in B&W chemistry, you want to retain the silver image and remove only the unexposed/undeveloped residual halides. Fixing in this case shouldn't take much longer than a regular B&W film.

That's blixing -- but C-41 originally had a bleach step (convert developed silver back to halide) and then a fixer step (dissolve the halide, just like in B&W). Even then, the fixer step is longer than normal B&W fixing with rapid fixer.

Huss · Aug 24, 2020

Looks like XP2 works much better than BW400CN in DF96. Mine was 77degrees for 14 minutes, intermittent agitation. Unusable results.

Donald Qualls · Aug 24, 2020

Raghu Kuvempunagar said:
Curious to know if you checked the film in complete darkness using night vision IR goggles. Wouldn't inspecting an insufficiently fixed film with lights on result in fogging when the film is put back in the monobath?

Sorry, I missed this on the first run-through, Raghu. No, I was in room light; I presume there was a little fogging (which might account for the odd contrast curve), though the rebates still look clear. One important thing that happens is that development partially desensitizes the halide -- all the sensitizing dyes (both for color and for speed enhancement) are washed out. This makes the emulsion quite slow, and sensitive only to blue light, and there isn't much of that in my incandescent room lights; that's probably why I don't have fogging I can actually see in the clear film areas. If I'd thought about it at the time, I had a bottle of rapid fixer in the cabinet under the darkroom counter; I could have just pulled that out, poured it over the film, and avoided the entire question.

Donald Qualls · Aug 24, 2020

Huss said:
Looks like XP2 works much better than BW400CN in DF96. Mine was 77degrees for 14 minutes, intermittent agitation. Unusable results.

I agree -- if not for the "not quite fixed" issue, I think it would have lived up the XP2's reputation when processed in HC-110.

At this point, pending results of another test roll in B&W chemistry, the main thing keeping XP2 from being my go-to ISO 400 film is cost. I can shoot 3 rolls of .EDU Ultra 400 for the cost of 2 rolls of XP2, and unlike some, I don't find it to be a full stop below box speed. There is surely a possibility I might get a bulk roll, though, once I get a couple rolls of 35mm under my belt.

Raghu Kuvempunagar · Aug 25, 2020

Huss said:
Looks like XP2 works much better than BW400CN in DF96. Mine was 77degrees for 14 minutes, intermittent agitation. Unusable results.

@Huss: If you have a Ferricyanide bleach with you, perhaps you can get something useful out of the BW400CN negatives using @David Lyga 's method. BTW the problem you faced has nothing to do with DF96. It's a problem one encounters while developing most C41 films in any B&W chemistry. Most colour films have what is called Carey-Lea silver layer which gives a dense look to the developed C41 film. David's method removes this silver using a blix to get much better looking negatives. I've tried his method and I know from my own experience that it works fine. XP2 Super is different from other C41 films in this respect - it doesn't have the Carey-Lea silver layer and hence doesn't require any special post-processing.

It shouldn't be too hard to get decent results from XP2 Super + DF96 combination. Those who want to try this combination should do some testing to figure out what EI and processing regime gives the best result. I would pick a few normal contrast scenes and shoot at EI 100, 200 and 400 and develop for normal contrast. The film works fine with any decent B&W developer including Thornton Two Bath, XTol, Pyrocat-HD, Obsidian Aqua and Adox MQ Borax. HC-110 is of course known to work well as evident from @drmoss_ca's work. Even my own experimental developer gives very decent result with XP2 Super.

Donald Qualls · Aug 25, 2020

Raghu Kuvempunagar said:
It shouldn't be too hard to get decent results from XP2 Super + DF96 combination. Those who want to try this combination should do some testing to figure out what EI and processing regime gives the best result. I would pick a few normal contrast scenes and shoot at EI 100, 200 and 400 and develop for normal contrast. The film works fine with any decent B&W developer including Thornton Two Bath, XTol, Pyrocat-HD, Obsidian Aqua and Adox MQ Borax. HC-110 is of course known to work well as evident from @drmoss_ca's work. Even my own experimental developer gives very decent result with XP2 Super.

If it works well in one developer, it'll work well in at least some others. I plan to process some in Xtol-R stock and compare it to C-41 soon. Based on the HC-110 time, it looks like same development as Tri-X, same fixing as T-Max 400.

Raghu Kuvempunagar · Aug 25, 2020

Donald Qualls said:
I plan to process some in Xtol-R stock

EI:160 51/2 minutes @20C works fine for me. YMMV.

Donald Qualls · Aug 25, 2020

Looks like 7 minutes and EI 400 will work well, too. I don't generally down-rate films; I make an effort not to meter optimistically. I generally have good shadow detail at box speed, so I also don't have an incentive to change my ways.

Huss · Aug 25, 2020

Raghu Kuvempunagar said:
@Huss: If you have a Ferricyanide bleach with you, perhaps you can get something useful out of the BW400CN negatives using @David Lyga 's method. BTW the problem you faced has nothing to do with DF96. It's a problem one encounters while developing most C41 films in any B&W chemistry. Most colour films have what is called Carey-Lea silver layer which gives a dense look to the developed C41 film. David's method removes this silver using a blix to get much better looking negatives. I've tried his method and I know from my own experience that it works fine. XP2 Super is different from other C41 films in this respect - it doesn't have the Carey-Lea silver layer and hence doesn't require any special post-processing.

It shouldn't be too hard to get decent results from XP2 Super + DF96 combination. Those who want to try this combination should do some testing to figure out what EI and processing regime gives the best result. I would pick a few normal contrast scenes and shoot at EI 100, 200 and 400 and develop for normal contrast. The film works fine with any decent B&W developer including Thornton Two Bath, XTol, Pyrocat-HD, Obsidian Aqua and Adox MQ Borax. HC-110 is of course known to work well as evident from @drmoss_ca's work. Even my own experimental developer gives very decent result with XP2 Super.

Thanks Raghu. I don't have anything like ferricyanide bleach (sounds scary!) and that is ok, because the intention of this thread is what works with DF96, w/o having to introduce other chemicals into the mix!
Takes away the point of using a monobath!

Donald Qualls · Aug 25, 2020

Given that rapid fixers carry a warning about overfixing dissolving image silver, it's just possible that leaving your film in the Df96 for way too long might dissolve that silver filter layer from the BW400CN. No extra chemicals, just an extreme example of needing to extend process time well past the end of development in order to get the best results.

Raghu Kuvempunagar · Aug 25, 2020

Donald Qualls said:
Given that rapid fixers carry a warning about overfixing dissolving image silver, it's just possible that leaving your film in the Df96 for way too long might dissolve that silver filter layer from the BW400CN. No extra chemicals, just an extreme example of needing to extend process time well past the end of development in order to get the best results.

If that's true then extended time in the monobath might also dissolve the silver image or at least the low density regions of it. Isn't it?

Raghu Kuvempunagar · Aug 25, 2020

Huss said:
Thanks Raghu. I don't have anything like ferricyanide bleach (sounds scary!) and that is ok, because the intention of this thread is what works with DF96, w/o having to introduce other chemicals into the mix!
Takes away the point of using a monobath!

Oh it's not as scary as it sounds. Infact ferricyanide bleach has been an essential chemical in all darkrooms since long. It is widely used to lighten dense areas in the print (and hence called liquid light) and in toning the print.

My suggestion to use ferricyanide bleach was only to salvage your bw400cn negatives which turned up too dense and useless after developing in DF96. Otherwise it doesn't make much sense to develop bw400cn and other C41 films with the silver layer in a monobath as you rightly said.

Donald Qualls · Aug 25, 2020

Raghu Kuvempunagar said:
If that's true then extended time in the monobath might also dissolve the silver image or at least the low density regions of it. Isn't it?

Generally, image silver will be larger grains than the silver layer referenced above, found in most C-41 films. Rapid fixers are mainly a "danger" to the smallest silver grains -- I've heard of (but never seen, because I've avoided overfixing) damaged to image silver in microfilm stocks, but in ordinary films, at most, it might lose a very small amount of shadow density -- which is inaccessible anyway if you're trying to print or scan through the silver filter or antihalation layer.

There are a few B&W films with a similar layer -- Fomapan 100R has a colloidal silver antithalation layer, which in the recommended reversal process bleaches away. Reports are, however, that the film makes good negatives, so it may be that the silver in that layer is fine enough for rapid fixer to remove some or most of it.

Huss · Aug 25, 2020

Raghu Kuvempunagar said:
Oh it's not as scary as it sounds. Infact ferricyanide bleach has been an essential chemical in all darkrooms since long. It is widely used to lighten dense areas in the print (and hence called liquid light) and in toning the print.

My suggestion to use ferricyanide bleach was only to salvage your bw400cn negatives which turned up too dense and useless after developing in DF96. Otherwise it doesn't make much sense to develop bw400cn and other C41 films with the silver layer in a monobath as you rightly said.

Thanks, it was a test roll that did not have anything of value on it. So no great loss.

Raghu Kuvempunagar · Aug 26, 2020

Donald Qualls said:
There are a few B&W films with a similar layer -- Fomapan 100R has a colloidal silver antithalation layer, which in the recommended reversal process bleaches away. Reports are, however, that the film makes good negatives, so it may be that the silver in that layer is fine enough for rapid fixer to remove some or most of it.

Has anyone really got good negatives from Fomapan 100R without bleaching? Can you provide some pointers to the same? Interestingly, Fotoimpex says this about the film on its website: "The Fomapan R can NOT be developed as a standard BW negative Film, because the anti-halation layer does not dissolve in the standard BW chemistry."

Donald Qualls · Aug 26, 2020

I've read anecdotal reports along the lines of "I tried it as negative, and it looks fine." Don't recall who or where, and they didn't give any process details. I'm going to go with "bleaching required" and "needs an extra stop of exposure to protect shadow detail."

If I were shooting B&W cine, it'd be a top choice (though it always seems there isn't enough light, so Double X or Tri-X -- Negative or Reversal, depending on format availability -- would likely be the primary choice).

Raghu Kuvempunagar · Aug 26, 2020

Donald Qualls said:
I've read anecdotal reports along the lines of "I tried it as negative, and it looks fine." Don't recall who or where, and they didn't give any process details. I'm going to go with "bleaching required" and "needs an extra stop of exposure to protect shadow detail."

Interesting! The only anecdotal reports I could find were exactly the opposite - negatives are too dense. I hope those who did get great negatives from Fomapan R100 will chime in and enlighten us on what they did to get usable negatives.

Donald Qualls · Aug 26, 2020

My thought is that it was more along the lines of "I forgot to mention the ten minutes in Farmer's Reducer and refixing to be able to see the images."

Huss · Aug 27, 2020

Leica M3 DS, Summaron 35mm 3.5, Ilford HP5+, DF96.

Cinestill DF96 monobath

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