A few drops Photoflo

RattyMouse · Mar 30, 2018

I've read many times posts where people say they just use a few drops of Photoflo when they are doing their final rinse. Today I decided to try something similar to that. I developed two rolls of Acros in 600 mls of fluid and for my final rinse, instead of doing the typical 1:200 dilution of Photoflo, I added 7-8 drops which is more than a few.

When I hung my film I saw clear signs that the wetting agent was doing nothing. Water all across the film was beading up. The surface tension of the water was not lowered anywhere near enough for the liquid to thin out and drain off the film. I am preparing for a pretty miserable amount of drying marks.

It's my own fault for trying this. It goes against everything I know as a surfactant scientist of the past 23 years. The concentration of surfactant in the water is nowhere near the critical micelle concentration which is where maximum lowering of the surface tension occurs.

There's a reason why Kodak recommends 1:200.

Sirius Glass · Mar 30, 2018

Finally someone gets it!

jtk · Mar 30, 2018

I've used 2-3 (two to three) drops per 10 second dip in 16oz Nikor tank in all sorts of water (from distilled to creek) for centuries.. now I use bottled water for that brief dip. Same sort of casual proportion and treatment with 4X5 hangers in 5 gal tanks. NEVER had water marks.

I thought everybody knew to use that water as a DIP, not WASH. It's best to learn from human beings rather than from data sheets. If Kodak's experts were so smart, why did they live in Rochester?

BAC1967 · Mar 30, 2018

I do 1:200 in distilled water and never have any problems with water leaving marks. Like jtk said, just a final wetting with that solution is all that's needed before hanging the film to dry. No need to squeegee the film either.

Svenedin · Mar 30, 2018

RattyMouse said:
I've read many times posts where people say they just use a few drops of Photoflo when they are doing their final rinse. Today I decided to try something similar to that. I developed two rolls of Acros in 600 mls of fluid and for my final rinse, instead of doing the typical 1:200 dilution of Photoflo, I added 7-8 drops which is more than a few.

When I hung my film I saw clear signs that the wetting agent was doing nothing. Water all across the film was beading up. The surface tension of the water was not lowered anywhere near enough for the liquid to thin out and drain off the film. I am preparing for a pretty miserable amount of drying marks.

It's my own fault for trying this. It goes against everything I know as a surfactant scientist of the past 23 years. The concentration of surfactant in the water is nowhere near the critical micelle concentration which is where maximum lowering of the surface tension occurs.

There's a reason why Kodak recommends 1:200.

I use a similar agent, Tetenal Mirasol. I measure it according to the instructions using a syringe.

Billy Axeman · Mar 30, 2018

I believe most of the problems arise with calcium deposits so I combine the wetting agent with demineralized water.

Svenedin · Mar 30, 2018

Billy Axeman said:
I believe most of the problems arise with calcium deposits so I combine the wetting agent with demineralized water.

So do I. My tap water very hard.

removed account4 · Mar 30, 2018

very weird RM
i have never used "the stated bottle dilution",
and as i have stated in previous threads on this topic
for decades ... couple of drops in a tank or tray worked fine.
photo teacher i had back in the day wouldn't permit the students to mix
the photo flow he would have the kids present him the tank with water + film
and he or the lab proctor would dispense a couple of drops. i asked him why
he said the dilution on the bottle was too strong, students were getting problematic
negatives, a few drops worked just fine ...
im glad you found a method that works for you, thats what its all about anyways.

twelvetone12 · Mar 31, 2018

Why should it be weird? Do you think manufacturers write random dilutions on the bottle? I, like RattyMouse, solved all negative drying problems when I followed manufacturer dilutions.

mshchem · Mar 31, 2018

I agree with Ratty follow the instructions . I've used photoflo for decades, where tap water is hard I use purified water. The old small glass bottles with a metal cap called for a capful in 20 fl. oz. of water. Cap held about 3 cc, 20 ounces is about 600mL. 1:200 . Case closed .

Doremus Scudder · Mar 31, 2018

Ratty,

I'm surprised you didn't take your negs down and treat them in a properly-diluted solution of Photo Flo before they dried with spots after you noticed that the water was beading up...

RattyMouse · Mar 31, 2018

Doremus Scudder said:
Ratty,

I'm surprised you didn't take your negs down and treat them in a properly-diluted solution of Photo Flo before they dried with spots after you noticed that the water was beading up...

I should have, but was worried that getting those lone 35mm strips of film back into a small Patterson tank without a reel might damage them.

RattyMouse · Mar 31, 2018

jnanian said:
very weird RM
i have never used "the stated bottle dilution",
and as i have stated in previous threads on this topic
for decades ... couple of drops in a tank or tray worked fine.
photo teacher i had back in the day wouldn't permit the students to mix
the photo flow he would have the kids present him the tank with water + film
and he or the lab proctor would dispense a couple of drops. i asked him why
he said the dilution on the bottle was too strong, students were getting problematic
negatives, a few drops worked just fine ...
im glad you found a method that works for you, thats what its all about anyways.

It was clear as day that 10 drops into 500 mls of water did NOTHING to slower the surface tension of the water. Nobody could have looked at my film and suggested it would dry quicker or more evenly than without the Photoflo.

Svenedin · Mar 31, 2018

RattyMouse said:
I should have, but was worried that getting those lone 35mm strips of film back into a small Patterson tank without a reel might damage them.

If you still had the film as one long strip you could dunk in a final rinse using a loop. You hold one end of the film in either hand to make a loop and bring that loop through the liquid. If the film has dried any drying marks can very hard to remove so if it seems the water is not sheeting off it’s best to act promptly. Hope your negs are OK.

Billy Axeman · Mar 31, 2018

I always do it that way. I have a small fridge box for it, about 12x12 cm, fill it with 2 cm of demineralized water + a few drops of wetting agent and zig-zag the film through it for 1/2 minute. If your arms are too short unroll the film for 50% and zig-zag both ends in succession. When you are ready let the box dry and put the cover on to keep dust out.

As has been said many times before, it's better not to use a wetting agent in your tank. Why would you risk any side effects.

I actually always see water beading up on my film (HP5+, Amaloco H10 wetting agent) and I have never problems with spots. I guess when the film surface is very smooth (on the back) it's difficult for the water to flow out smoothly because it always has some residual surface tension, but when you use demineralized water it's no problem.

cornflower2 · Mar 31, 2018

I use a 5 micron water filter on my tap wash water and add several drops of Photoflo to a 1L jug to make a modest/weak bubbly 'head' on the water, that's how I judge its strength as being adequate. Then I see-saw the whole 135/120 film through as a U-loop and I make sure it gets thirty seconds of it. Then I hang up to dry and usually squeegee using a nice old Agfa squeegee fitted with white rubber inserts. Probably better not to squeegee, but I always do. I once went for a while without using Photoflo and found that the squeegee was leaving all sorts of weird silvery deposits on the film, so the Photoflo definitely acts as a lubricant if you're squeegeeing, and either way is essential.

Pentode · Mar 31, 2018

RattyMouse said:
There's a reason why Kodak recommends 1:200.

Yeah, more often than not I find that the manufacturer's directions are pretty well thought out.
I use the suggested 1:200 solution with distilled water and I never have problems. No squeegeeing necessary and my negatives are unharmed.
I use the wetting agent (Photo Flo) right in the tank with the reels and agitate very, very gently by just turning the reels back and forth a little.
I clean everything really well with mild soap and hot water and I haven't had issues with the Photo Flo contaminating anything.
It's possible that I could get away with a slightly weaker solution, but I see no reason to fix something that isn't broken. Not for me, anyway.

jtk said:
If Kodak's experts were so smart, why did they live in Rochester?

On the other hand, jtk makes an excellent point!

Bill Burk · Mar 31, 2018

RattyMouse,

Can you describe your water? I use reverse-osmosis filtered water for the final dip.

I estimate I use Photo-Flo at very nearly 1:2000 which is an absurd dilution that I should not recommend to others.

I use 0.25 - 0.30 ml Photo-Flo (I use a syringe I got from the veterinarian when I had to give antibiotics to a pet rat) to about 16 ounces of water in a porcelain tray. I remove the film from reels then see-saw the film though this bath a couple of times, then immediately hang it.

Tap water here, even though it's filtered with a one-stage cartridge, typically has too much crud in it. I have had dirty negatives after rinsing in tap water with this dilution of Photo-Flo, so I switched the water.

Alan Johnson · Mar 31, 2018

RattyMouse said:
It was clear as day that 10 drops into 500 mls of water did NOTHING to slower the surface tension of the water. Nobody could have looked at my film and suggested it would dry quicker or more evenly than without the Photoflo.

10 drops into 500ml DEMIN water with 25 ml isopropyl alcohol has worked fine for me for years.
I pull the negatives at an angle when drying so any runs go off the negative area.
The IPA stops bugs growing in the solution which is. reusable for many films.
Perhaps Kodak refers to the use of tap water.

RattyMouse · Mar 31, 2018

Alan Johnson said:
10 drops into 500ml DEMIN water with 25 ml isopropyl alcohol has worked fine for me for years.
I pull the negatives at an angle when drying so any runs go off the negative area.
The IPA stops bugs growing in the solution which is. reusable for many films.
Perhaps Kodak refers to the use of tap water.

Why in god's name would you reuse a solution like this? I have a bottle of Photoflo that is almost 3 years old and still 85% full. It will take me a decade to use this whole bottle up.

Alan Johnson · Mar 31, 2018

RattyMouse said:
Why in god's name would you reuse a solution like this? I have a bottle of Photoflo that is almost 3 years old and still 85% full. It will take me a decade to use this whole bottle up.

I don't want to use 500ml demin water for each film, saves having to keep going out to buy it.

RattyMouse · Mar 31, 2018

Alan Johnson said:
I don't want to use 500ml demin water for each film, saves having to keep going out to buy it.

Ok, that makes sense. I forget not everyone can get DI water free as I can. Our lab makes it every day by the ton.

AgX · Mar 31, 2018

RattyMouse said:
... as a surfactant scientist of the past 23 years.

Then I even wonder more that you do not mix your own wetting agent.

faberryman · Mar 31, 2018

Ratty, you are upsetting the finger in the wind photographers with your science.

paul ron · Mar 31, 2018

RattyMouse said:
I've read many times posts where people say they just use a few drops of Photoflo when they are doing their final rinse. Today I decided to try something similar to that. I developed two rolls of Acros in 600 mls of fluid and for my final rinse, instead of doing the typical 1:200 dilution of Photoflo, I added 7-8 drops which is more than a few.

When I hung my film I saw clear signs that the wetting agent was doing nothing. Water all across the film was beading up. The surface tension of the water was not lowered anywhere near enough for the liquid to thin out and drain off the film. I am preparing for a pretty miserable amount of drying marks.

It's my own fault for trying this. It goes against everything I know as a surfactant scientist of the past 23 years. The concentration of surfactant in the water is nowhere near the critical micelle concentration which is where maximum lowering of the surface tension occurs.

There's a reason why Kodak recommends 1:200.

+1

A few drops Photoflo

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