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