life of photo flo

[paulbarden]

It is meant to be used once and discarded. You can save it and reuse it if you are developing multiple rolls of film in the same session/same day, but don't bother saving it for reuse beyond the day you mixed it. I mean, it's so inexpensive - a small bottle will last for years.

Also, I wouldn't give a lot of credence to these experimental "recipes" you find on the web. There is no compelling reason to add alcohol to Photo Flo if you're using it correctly.

[Michael R]

BS No Soap

Ok but what I mean is that the wetting agent isn’t just for water quality. It’s for preventing water from beading up because that can result in what Kodak termed “differential drying” of the emulsion, which can potentially lead to permanent defects under the right circumstances. The surfactant breaks the surface tension of the water so it slides off instead of forming droplets.

[nolindan]

I find isopropanol (isopropyl alcohol) helps with sheeting the water off the film.

I make up a stock solution of 13ml PhotoFlo 600 (40ml of PhotoFlo 200) in 1 liter of isopropanol. This gets diluted down 1:7 with distilled water - the ratio was chosen as it is an easy 1 oz of stock per reel, assuming SS tanks.

Talk about a century's worth - I have a gallon of PhotoFlo 600 I got at a clearance sale - enough for 600 gallons of working solution or 9,600 rolls of film. I'd have to shoot 2 rolls of film a week for the next hundred years.

[Drew Wiley]

Why would something as basic as wetting agent have changed its formula? You only need a few drops of it each session. I took me almost 20 years to use a single bottle of Photofo. The Ilford equivalent I'm currently using should last me another decade or more. It doesn't go bad. But don't pre-dilute and re-use it. Water mold will grow in there.

[djdister]

I've been using the same small bottle of Photo-Flo for over 10 years, 1-2 drops at a time...

[monochromeFan]

Why would something as basic as wetting agent have changed its formula? You only need a few drops of it each session. I took me almost 20 years to use a single bottle of Photofo. The Ilford equivalent I'm currently using should last me another decade or more. It doesn't go bad. But don't pre-dilute and re-use it. Water mold will grow in there.

Thats the reason the photrio recipe used the 200ml of 91% alcohol... NOTHING grows in it. And even after all this time, anytime i open the lid the whole bathroom stinks like cheap vodka.

Im also kind of happy and scared at my progress.

[Tin Can]

The photographer who doesn't use something like Photo Flo probably makes up for that by using more Spotone. Photo Flo is much less trouble, especially when used in distilled water.

I never Spot wet prints

I hate DIGI repair

My studio my rules

I embrace my reality

[Doremus Scudder]

What is the general thought on when one should get rid of the current batch of mixed working stock photo flo?

Use it one session. Diluted Photo Flo (and most other wetting agents) grow bacterial slime after a day or so. It's cheap, use it fresh.

Doremus

[Mark Sampson]

When I ran the roll film sink line in a custom lab, long ago, the established practice was to change the 1-gallon Photo-Flo tank weekly. And "purge" the stainless reels in 100F water to remove any P-F residue, which interferes with the developing process. I was well-trained there, and continued those practices when I worked in another lab, and again at EK.
45 years later, I've been using the same tiny bottle of P-F's Edwal equivalent for a decade. Two drops of concentrate per film run lasts a while. When it's gone I have a 4 oz. bottle of Photo-Flo 200 that will last the rest of my life.
Yes, bacteria will grow in Photo-Flo over time.
No, it's not worth saving for re-use. It's literally pennies per liter.

[Drew Wiley]

Not technically bacteria; water mold (Saprolegnia). Just as obnoxious, requiring you to filter the solution.