How I learned to stop worrying and love the drying marks...

[mshchem]

We need a good Practical Physicist. The concentration of the surfactant is optimized at recommended strength. Purity of water shouldn't matter.
I have a bottle of Isopropyl Alcohol 91%, I'm going to follow Matt's recommended preparation of a stock solution to make measurement exact. No more half a cap etc etc.

 

[MattKing]

I usually mix up my working strength Photo-flo while the developing tank is on the rotary agitator during the first half of the fixing stage.
So the Photo-flo has a few minutes to come to equilibrium before I use it - I can even agitate it a bit and there will still be enough time for any bubbles to subside into nothingness.

 

[faberryman]

I usually mix up my working strength Photo-flo while the developing tank is on the rotary agitator during the first half of the fixing stage.

I don't have a rotary agitator so I mix up my Photoflo while the film is under the faucet washing.

 

[Sirius Glass]

Ultra pure water once exposed to air is very susceptible to biofilms. Chlorine in tap water helps to reduce growth. Fuji and others make biocide tablets to use with their deionizer.

And tap water has clorine and other chemicals to kill bacteria and microbes. I use tap water which is very hard and with PhotoFlo I have had no spotting or streaks.

 

[Don_ih]

Just use Palmolive. It's soft on hands while you do dishes.

 

[Moose22]

1cc of Photo-Flo in 500cc of water doesn't sound like much even if you type it in a 24 point font. Kodak recommends 1 part Photoflo to 200 parts water which is 2.5cc per 500cc water, so Bill is suggesting a lot less than Kodak. I have no idea how much "a few drops" is. I guess it depends on the size of the drops. I use distilled water and usually don't have a problem with spots. When I do, they are usually on the base side of the film and come off with a little alcohol and a cotton swab.

I use one plastic pipette per liter. About 4cc (cheap pipettes, not super precise so 3.5-4mlish). Works like a charm, but it's under half the recommended.

I never changed it once I realized I was doing like 40% of the expected concentration because, in the spirit of this thread, why worry?

It works really well, the full strength I tried one time didn't work any better. I mix it up while I'm working, always do a liter at a time because that's how big my tank is and how bug my flasks are. I'm super precise at xtol time, reasonably careful with the fixer, and I have a rinsing process I follow, but the way I see it precision gets less important as the development process continues. This isn't something to worry about.

 

[koraks]

To be fair, you can thoroughly homogenize a Photoflo solution in a few seconds with vigorous agitation

Stirring for a few seconds with a glass rod will do the trick just fine and won't create problematic foaming.
Despite the academically interesting observation about thermodynamics, I just don't see the need for mixing flo wash 30-60 minutes in advance. Not that it hurts, but it won't help anything either.

 

[faberryman]

Stirring for a few seconds with a glass rod will do the trick just fine and won't create problematic foaming.

Is their something special about a glass rod? I just use the plastic paddle I use to mix up the other stuff and it seems to work fine.

 

[koraks]

Is their something special about a glass rod?

Not really.
A glass rod works very well, but evidently just about anything will do. We could debate long and deep about materials, shapes, turbulence etc., but that would be beside the point.

 

[Don_ih]

Is their something special about a glass rod? I just use the plastic paddle I use to mix up the other stuff and it seems to work fine.

Pretty much don't use anything porous, like a used Popsicle stick. Glass rods (and plastic ones) clean off easily.

If you use a used Popsicle stick, probably throw it away after that.

 

[Bill Burk]

I did some experiments increasing the concentration. I probably still had my reverse osmosis filter at the time, that’s the water I used. (Now I use bottled distilled water).

The old “few drops” obviously was not enough to create a sheeting action on base or emulsion.

1cc to 500cc sheeted very nicely both sides. The difference was dramatic.

I don’t know if I tried 1:200 but assumed Kodak wanted to increase the margin of safety.

 

[Sirius Glass]

Just use Palmolive. It's soft on hands while you do dishes.

Search Photrio and you will see that PE especially said not to use dishwashing soaps since they contain perfumes and other chemicals that can be damaging to film. He spent years posting warning about that, so please do not propagate that harmful in formation. I might work for you and later you may discover damage. Do not make newbees fall into that trap!

 

[Don_ih]

Search Photrio and you will see that PE especially said not to use dishwashing soaps since they contain perfumes and other chemicals that can be damaging to film. He spent years posting warning about that, so please do not propagate that harmful in formation. I might work for you and later you may discover damage. Do not make newbees fall into that trap!

It was a joke - a reference to an old commercial - and a sideways way of saying "Who gives a F___?"

I.E., all those wetting agents are the same. They all do the same thing. There's no magic formula. Use some, flick as much water off the film as you can without kinking the film, hang the film up and wait. If there are water marks, rub them off.

 

[ags2mikon]

Thanks Don. I just went out and bought 3 bottles of Palmolive for the darkroom. I'm afraid to give them to the wife, she might insist that I use it for it's intended purpose. I got the sarcasm.

 

[Don_ih]

Thanks Don. I just went out and bought 3 bottles of Palmolive for the darkroom. I'm afraid to give them to the wife, she might insist that I use it for it's intended purpose. I got the sarcasm.

I hear it's GREAT for adding alkalinity to developer. Mix it with some Sanka and you're ready to roll.

 

[ags2mikon]

Drink it and you'll be ready to trot!

 

[Sirius Glass]

It was a joke - a reference to an old commercial - and a sideways way of saying "Who gives a F___?"

I.E., all those wetting agents are the same. They all do the same thing. There's no magic formula. Use some, flick as much water off the film as you can without kinking the film, hang the film up and wait. If there are water marks, rub them off.

Where are the tags, [sarcasm] [/sarcasm] or [joke] [/joke] so newbees do not get mislead?

 

[mshchem]

Just use Palmolive. It's soft on hands while you do dishes.

Yes. "You're soaking in it"

 

[mshchem]

goniometer water contact angle - Google Search

 

[Huss]

I did some experiments increasing the concentration. I probably still had my reverse osmosis filter at the time, that’s the water I used. (Now I use bottled distilled water).

The old “few drops” obviously was not enough to create a sheeting action on base or emulsion.

1cc to 500cc sheeted very nicely both sides. The difference was dramatic.

I don’t know if I tried 1:200 but assumed Kodak wanted to increase the margin of safety.

So how many bubbles on the surface indicates correct concentration?

 

[Jay Schrotenboer]

I use one plastic pipette per liter. About 4cc (cheap pipettes, not super precise so 3.5-4mlish). Works like a charm, but it's under half the recommended.

I never changed it once I realized I was doing like 40% of the expected concentration because, in the spirit of this thread, why worry?

It works really well, the full strength I tried one time didn't work any better. I mix it up while I'm working, always do a liter at a time because that's how big my tank is and how bug my flasks are. I'm super precise at xtol time, reasonably careful with the fixer, and I have a rinsing process I follow, but the way I see it precision gets less important as the development process continues. This isn't something to worry about.

Actually your usage is 70-80% of the recommended amount, so you are not very far off

 

[bags27]

I did all the right things (LFN, distilled water, etc), and it worked well for B&W. But for whatever reason, color film, especially expansive blue skies, often had watermarks. Someone here suggested kimwipes and OMG! Haven't seen a watermark since.

 

[Sirius Glass]

I did all the right things (LFN, distilled water, etc), and it worked well for B&W. But for whatever reason, color film, especially expansive blue skies, often had watermarks. Someone here suggested kimwipes and OMG! Haven't seen a watermark since.

Almost as effective as course sandpaper or emery paper.

 

[mshchem]

Almost as effective as course sandpaper or emery paper.

Real damage is best achieved with a squeegee.

 

[Helios 1984]

I did all the right things (LFN, distilled water, etc), and it worked well for B&W. But for whatever reason, color film, especially expansive blue skies, often had watermarks. Someone here suggested kimwipes and OMG! Haven't seen a watermark since.

Which C-41 kit do you use?