Photo Flo In Presoak OK for PMK?

[John Layton]

While for some time now I've been adding a bit of Photo-Flo to my presoak before souping films in Pyrocat-HD, I'm about to give PMK another go after a bit of a hiatus.

Question - any others who either add photo-flo to their pre-soaks, or who are too cautious to do this...care to comment on any evidence that Photo Flo carried over into the PMK solution (or Pyrocat, for that matter) might possibly interfere with the developers uptake/efficacy, and/or compromise results in any way? I cannot find any references to this, and am just curious!

[Mark Sampson]

When processing sheet film in trays, a presoak in a 1% solution of Kodalk will keep the sheets of film from sticking together. That's been my practice for decades now.
I don't know where the idea of using Photo-Flo as a presoak comes from; Kodak never mentions it. But if it works with one developer, it will probably work with another.
A side note. In the late '70s I was a tech in a custom lab. I processed many rolls a week (2x daily) in stainless tanks & reels. The reels, loaded with wet film, were dunked in a tank of Photo-Flo as a last step. The procedure in that lab was to weekly "purge" the reels and hangers in 100F running water, "to keep the Photo-Flo residue from contaminating the developer". One didn't question procedures in that lab, or ask "why" very often; I did as I was instructed. But ever since I've made sure my tanks, reels, and hangers are clean.

[bmikiten]

My understanding is that Photoflo is a surfactant and as a result, would be a bad idea. Reducing the surface tension in a developer doesn't really have a purpose.

[paulbarden]

I cannot think of any good reason to pre-soak with a surfactant in the water. It’s interaction with any developer is a wild card, and one that I see no point in risking.

[Drew Wiley]

It might help the sheets not sticking together as much when slipped into the tray. But I use plain water and practice the poker hand method, with the sheets fanned out a little held in the dry hand, and taken one at a time by the wet hand, placed in the pre-wetting tray, and swished just a little to get the whole surface wet, before placing the next sheet in. Then a couple shuffles through the entire stack before proceeding to actual development.

[Vaughn]

I thought I read that one of the reasons Ilford does not suggest a pre-soak is that their film's emulsion already has a surfacant in it to aid an even reception of the developer into dry emulsion.

But this info needs back-up.

[Drew Wiley]

I've even developed sheets of FP4 in the same tray as Fuji ACROS since they both respond well to the same length of dev time. No difference in outcome at all versus developing them separately. I stopped worrying about rumors of built-in surfactants in certain Ilford films long ago, true or not, which specific films or not, because I've never seen even the slightest hint of that being a liability to my normal routine of pre-wetting procedure in either trays or drums. Perhaps too short a pre-wet would be unadvised; but I can't test for every possibility that doesn't apply to me personally.

[Don Dudenbostel]

In the early 70’s I asked my Kodak TSR about presoaking in a very dilute photoflo solution. The answer was absolutely not. I don’t remember the exact reason but the answer was never personal in photoflo. Mark is correct, photoflo leaves a residue on stainless reels and hangers and should be washed off before putting them back in developer. I wash mine thoroughly after every use.

[Vaughn]

...No difference in outcome at all versus developing them separately. ...

I've never have worried about it. The amount of a surfactants in an emulsion should have no effect on other films in the tray/drum.

[Silvergrain]

Hello,
Besides sheet-film, I'm using photo-flo and the likes for roll-film rotating development. I put (a drop) of it in the developer with no pre-soak, which gives me very even development on 120 format; I guess this accelerate and invigorate the developer flow at the surface of the film, where it is "sucked" by the chemical reaction, and need a more punchy action to be dislodged as it becomes exhaused and be replaced by fresh developer save to get zoning.

According to Jobo, these surfactants are likely to accumulate on the plastics of the reels, hence scrubbing them under hot temperature is necessary if you want to avoid zoning on a short term horizon. So do I (but it is a pain to do it at the end of the development session). Looks similar to Mark's experience in his pro lab

[Drew Wiley]

Sometimes a tiny amount of EDTA in the dev might be better in terms of overall evenness of dev, if you can't control it in a more conventional manner.

[Rick A]

I've used a drop or two of Edwal LFN in my developer when using D-76 in small tanks to keep it from foaming, never in pre soak though.

[PRJ]

I can make a case for and against it. It just depends. Back in the day the only way to avoid air bells on HIE was to add LFN to the developer. On the other hand, LFN combined with glycol (if you mix your Pyrocat in Glycol) is a disaster with inversion developing. You might as well run a bubble bath. I imagine PhotoFlo would have a similar effect but I haven't used it in years so YMMV. I doubt there would be a problem in tray processing though.

If you have not had any problems with PhotoFlo with Pyrocat I can't think of a reason why PMK would be any different. Then again if you don't have problems with air bells I don't see a reason to use it either.

[neil poulsen]

I thought I read that one of the reasons Ilford does not suggest a pre-soak is that their film's emulsion already has a surfacant in it to aid an even reception of the developer into dry emulsion.

But this info needs back-up.

Also my understanding after speaking with an Ilford technician. He said that the film contains wetting agents. So, I don't use a presoak with that film.

[Drew Wiley]

Neil - we're going around in circles on that one. It's been repeatedly addressed in numerous previous posts. Since I've charted these water for decades myself, it's "Damn the torpedoes, full stem ahead!" Ilford film is no different than any other brand in this respect, and I always pre-wet that too, every type. A case has been made elsewhere for certain microfilms and their specialty developers not to pre-wet, but that's an outlier topic. I even routinely pre-wetted for TechPan with total success.

Maybe Ilford was just trying to improve the odds of those who don't take the extra step of pre-wetting, and was using this as a feather in their marketing cap. But that in itself is not a negation of the positive value of pre-wetting. No different than their tech shees recommending this or that developer which they specifically market as well. Doesn't mean many other developers don't work equally well, or perhaps even better.

[Michael R]

There are basically two situations in which pre-soaking is of possible merit. (1) where the film cannot be uniformly wetted with developer in a short amount of time, (2) where film surfaces might come into contact before they are thoroughly wet.

Ilford advises against pre-soaking in general since it results in removal of the incorporated wetting agent. This will really only potentially matter in cases where the film will not be immersed in the developer quickly/uniformly.

[Tin Can]

Agree

No presoak

No soap either

[Greg]

When I was a student at The Rochester Institute of Technology in the 1970s, I took a course in Photographic Sensitometry under Prof. Hollis Todd and Prof. Hill. The topic of using a Photo Flo solution in the presoak came up. I do remember that it was a definite NO to do this... sorry I can't recall the reason why. Possibly not to use with automated processors? The "current" thinking back then was actually not to presoak the film, but to start the development process by putting the film directly into the developer with a full minute of continuous agitation. For me, I have always used a plain water presoak per the recommendation of possibly George E. DeWolfe.

[esearing]

my rule of thumb for FP4 and HP5 - Presoak in plain water if using diluted developer or developer can not be added to tank within 10 seconds, not required if using full strength or small tanks/trays. It can take me 45 seconds to fill an 1800ml tank for my 5x12 and 15 seconds for the SP445, so I always presoak for about 5 mins; which gives me time to adjust water to final temperature and add the parts A and B for Pyrocat M . The presoak seems to do a good job of removing the dye so it doesn't end up coloring my fixer.

I have eliminated photoflo entirely but have good water quality and do not get water spots.

[Tin Can]

Thanks for your complete answer

It makes sense, as it takes a long time to get it all wet

My process gets my film of any size fully in developer and wet in under 1 second to 3 seconds

Even 14X36" film


my rule of thumb for FP4 and HP5 - Presoak in plain water if using diluted developer or developer can not be added to tank within 10 seconds, not required if using full strength or small tanks/trays. It can take me 45 seconds to fill an 1800ml tank for my 5x12 and 15 seconds for the SP445, so I always presoak for about 5 mins; which gives me time to adjust water to final temperature and add the parts A and B for Pyrocat M . The presoak seems to do a good job of removing the dye so it doesn't end up coloring my fixer.

I have eliminated photoflo entirely but have good water quality and do not get water spots.

[Andrew O'Neill]

Yes, it will be okay with PMK. The only time I stick Photo-Flo in a developer these days is when I use Two-Bath Pyrocat-HD... in bath A. Helps reduce risk of mottling when going into Bath B. I've never seen mottling, so it must be working ;)

[Drew Wiley]

Bingo! Part of the problem is due to the design of certain brands of rotary tanks which simply fill and drain too slow. I can fill even a 30X40 inch print drum during rotation in 5 sec. That's due to superior drum design. Conversely, some practitioners might have in mind passive dunk tanks and film hangers, where submersion is almost instantaneous. Then there are those who do shuffling in trays - my preferred method for sheet film. Truly predictable results won't tolerate even a ten second variance between sheets. For truly fussy work like matched color separation negs or associated masks, the method and timing of the film sequence must be first-in, first-out, in exact order. So overall, there is no one generically correct answer, because we have somewhat different equipment and development protocols.

[Michael R]

Drew, good old shuffling in trays? I thought you of all people would have reclaimed whatever custom whiz bang jacketed xenon burst thing they used at JPL back in the day.

[Drew Wiley]

I done tried all them durn whizz-bang approaches, but then me gunpowdr get isself all wet in the derkness and cain't fire. If'n the Brits had knowed thet, they dasn't lost the Revulsionary War.