Df96 Monobath for Paper Prints

[laingsoft]

My wife is working early and needing a ride, so I found myself with a spare hour or two in the morning before I start working from home. I also had a bottle of DF-96 that i'm not really interested in using anymore, so I decided to try using it as a one-step paper dev/fix.

I had a pretty dark photo from an Ansco Panda toy camera to start with, I did f16 for 20 seconds on some expired Ilford Multigrade 4 RC.

According to what I've read both on here and on the Cinestill website, fixing speed is increased by agitation and developing speed is increased by either temperature or pH. I didn't adjust the temperature at all, so it was done at ~20C. I slipped it into the bath and let it sit until it looked developed(ish), then I started some light agitation for a few minutes until I saw no more change happening. Then rinsed with water.

You can ignore the big mark in the bottom, I didn't dry the paper properly as I ran out of clips. The top portion of the image is covered in a fine grit. I'm thinking this was the residual sludge that was in my DF96. It honestly looks a lot nicer digitally than it does in real life. The image looks very washed out. I don't know if that's due to an underexposure or because the monobath fixed the image too quickly.

Is it archival? I doubt it. Does it work? Kinda, is it worth it? No, I don't think so.

 

[Donald Qualls]

Does it work? Kinda, is it worth it? No, I don't think so.

I agree with your assessment. Paper has different developing and fixing rates from (most) film, and we are much more likely to develop to completion rather than stop development at a particular point to control contrast, as we do with film.

It might be possible to experimentally derive a temperature/agitation combination that would produce normal-looking prints with fresh Df96, but it has a capacity of only 16-20 8x10 equivalents for film, so a long printing session would be approaching exhaustion -- not to mention print development time running upwards of five minutes, possibly as high as ten, due to needing to compensate as the developer gets used up and the fixer loads with silver.

I quite like the way Df96 behaves on film. Last night, I processed a fresh roll of Cinestill BWXX pushed to 400, and in the same tank a roll of 1990s vintage Tri-X exposed in 2004, pushed to 800 -- and both gave good results, and (not counting time to warm everything up) both were ready for wash in six minutes. I'm sure I'll continue to use Df96, even after I have my darkroom operational enough to have other choices. But I won't use it for prints.

 

[Raghu Kuvempunagar]

Somebody on Facebook used this monobath for paper negatives and his results looked good.

 

[Donald Qualls]

Somebody on Facebook used this monobath for paper negatives and his results looked good.

For paper negatives you'd usually want lower contrast than for a final print -- meaning you wouldn't want to "push" things as much, to try to get development ahead of fixing.

 

[Raghu Kuvempunagar]

Perhaps adding a few tea spoons of Sodium Carbonate to the monobath might boost the developer activity relative to the fixer and get the job done.

 

[laingsoft]

Perhaps adding a few tea spoons of Sodium Carbonate to the monobath might boost the developer activity relative to the fixer and get the job done.

According to the MSDS Df-96 is a hydroquinone only developer, so it's likely a buffered Sodium Hydroxide solution. The easiest way of increasing development activity would be to increase the temperature imo

 

[Raghu Kuvempunagar]

It might have Phenidone or Dimezone in addition to Hydroquinone but in small quantity.

What's the pH of the working solution? If it's already high then adding carbonate won't make much difference.

Edit: pH is ~ 10.9 according to MSDS which is quite high already. Carbonate addition won't help.

 

[Donald Qualls]

The developer component of Df96 is equivalent to D96, which is a low contrast PQ developer originally intended for cine films. The amount of phenidone in the monobath is small enough, and its toxicity is low enough, they're not required to list it on the safety panel, but it's there. The stuff couldnt' get to full film speed in 3 minutes (at 80F) with hydroquinone only, and it would be prone to "infectious development" as well.

 

[Raghu Kuvempunagar]

Turns out that monobath for paper isn't an outrageous thought:

Back in the 1970's I researched and designed Monobaths for commercial use with a specialist emulsion, much of the initial work was done with resin coated papers and it was suggested that we market a Monobath for papers. However I found that the formula needed tweaking to suit different emulsions to get the best results.

i don't have access to my notes at present but you could start with Crawley's FX-6a, although it's a film developer it does work well with papers as well, but may need tweaking slightly:

Crawley FX-6a Monobath

Sodium Suphite 50.0 grams
Hydroquinone 12.9 grams
Phenidone 1.0 gram
Sodium Hydroxide 10.0 grams
Sodium Thiosulphate 90.0 grams
Water to 1 litre

Ian

It might be easier to tweak the above formula than try to get DF96 working for paper.

 

[Raghu Kuvempunagar]

The developer component of Df96 is equivalent to D96, which is a low contrast PQ developer originally intended for cine films.

Kodak D96 was a MQ developer iirc.

 

[laingsoft]

It might be easier to tweak the above formula than try to get DF96 working for paper.

If what Don said is true, and DF96 is a PQ developer, it should roughly be the same as that formula, barring the huge sulphite excess, which Cinestill probably saves by boiling the water first before using. If I had some Phenidone I would try it, but I've only got HQ at the moment.

 

[Donald Qualls]

Okay, I stand corrected -- Kodak D96 is indeed an MQ developer. How Cinestill gets away with leaving Metol (known skin irritant and potential sensitizing agent) off the SDS label is hard to understand. Perhaps they've reformulated with a tenth as much phenidone, as others have done in making "eco" developers. That would be only 0.15 g of phenidone per liter...

 

[Ian Grant]

Okay, I stand corrected -- Kodak D96 is indeed an MQ developer. How Cinestill gets away with leaving Metol (known skin irritant and potential sensitizing agent) off the SDS label is hard to understand. Perhaps they've reformulated with a tenth as much phenidone, as others have done in making "eco" developers. That would be only 0.15 g of phenidone per liter...

The major issue with Metol and skin irritation was due to impurities from its manufacture some companies had tackled and erased the problem before WWII, of course a very much smaller number of people might be sensitive to it, and many other photochemicals. The Hydroquinone is the more txic of the two.

Ian

 

[Donald Qualls]

The major issue with Metol and skin irritation was due to impurities from its manufacture some companies had tackled and erased the problem before WWII, of course a very much smaller number of people might be sensitive to it, and many other photochemicals. The Hydroquinone is the more txic of the two.

When I took photography in high school (1973-1974), there was a girl who broke out terribly, looked like her hands were burned, after the first time we made prints. It was genuine Dektol (with which I've never used protective gear and never had a problem) that did it. Good to hear it's been a solved problem (aside from what amounts to allergies) for decades, but there are still a bunch of warnings around...

 

[laingsoft]

According to EHSO, MSDS's only need to contain the information if the concentration is greater than 1%, or 0.1% if the compound is carcinogenic, which metol is not.

 

[Donald Qualls]

The formula I linked has only 1.5 g/L of metol and the same for hydroquinone -- yet the hydroquinone is on the hazmat label and the metol is not. Did HQ get labeled as carcinogenic while I was out of the darkroom?

 

[laingsoft]

No, apparently It's still group 3B. Very odd.

 

[Raghu Kuvempunagar]

Interestingly, Cinestill has a "new D96 B&W motion picture developer" product as well! It's MSDS mentions Hydroquinone, Sodium Sulphite and Borax but no Metol. Could it be that Cinestill replaced Metol by small amount of Phenidone or Dimezone?

 

[Anon Ymous]

What makes you guys think that DF96 definitely has metol? The fact that D96 does? These two developers are obviously radically different. The pH level alone is enough of a fact. Additionally, we're talking about a developer that is meant to be reused. Phenidone is much less affected by bromide content, so it should be easier to reuse it unreplenished. Phenidone, in the usually low concentrations used in developers, doesn't necessarily have to be included in an MSDS. So, if I had to make a bet, I'd say it's a PQ developer.

 

[Raghu Kuvempunagar]

What makes you guys think that DF96 definitely has metol?

Nobody said DF96 definitely has Metol. It's likely to be a PQ developer.

Otoh there are developers that have substantial Metol in them and yet have high pH. Edwards 20X for instance is one such developer.

 

[Anon Ymous]

Nobody said DF96 definitely has Metol. It's likely to be a PQ developer.

Otoh there are developers that have substantial Metol in them and yet have high pH. Edwards 20X for instance is one such developer.

Oh, the pH comment wasn't about development agent choice, it was about the fact that Df96 is a very high pH developer (10,85), while D96 has a pH of 8,6. After a bit more searching, the label on the Df96 bottle explicitly mentions that it contains Dimezone-S, a phenidone variant.

 

[Raghu Kuvempunagar]

Cinestill says DF96 is akin to D96 and it probably means they give similar results.