Homemade photo-flo or wetting agent?

Yeah... I heard that years ago too. Photo flo is cheap enough. I would never put soap on my film. I'm sure a lot of folks do it, but why? Get yourself some photo flo.
 
It seems to me I have heard that you can use liquid dish washing detergent, but why? I imagine a bottle of proper wetting agent costs maybe $6 and would probably last ya 300 years. :)
 
Just to recap:
Soap is made from animal fat and hydroxide. To make it pH neutral you have to add an acid. The mixture decomposes over time to release sulphur and other nasties detrimental to your negative. In addition, soap reacts with the dissolved salts in tap water to form an insoluble scum which can end up on your neg.
Detergents are manufactured from oil and are complex long chain molecules which again can break down over time. In addition, detergents contain other compounds designed to do different things - remember that they are designed for washing greasy dishes - which themselves decompose.
In both cases they have to be used at quite high concentrations in order to work effectively and this results in a sticky coating of soap/detergent remaining on the neg.
People who use soap or detergent and claim it works fine usually use it in such incredibly low concentrations that it does not actually do anything.

Wetting agent is normally ethylene glycol (it's used in car antifreeze). This compound has a relatively small molecular size, is chemically inert and is pH neutral. It tends to leave the neg along with the water - any residue is undetectable.
The bottom line is - use the proper stuff. If detergent or soap worked as a wetting agent then Kodak would use it. The fact that Kodak doesn't use it should tell you all you need to know.
 
Many decades of work in commercial/pro labs. I heard about this recipe, but never used it.

5 gal water (danger...your water might not be as clean as you think...)
1 oz dish soap
1 oz glycerin


Evidently the key is the glycerin. It adds a slippery element that prevents spotting.

Recipe above gives you a lifetime supply of course.

Earlier post on this thread was wise. Photo Flo is cheap. The only reason this conversation came up at work was because we were a very very busy lab, and always looking out for a way to save/make a dime. We ran about 300 rolls of 35 on an average day. Even with that volume, we decided to keep buying Photo Flo and not risk the experiment on other people's film. If you want to experiment on your own, go right ahead.

But...all this is really about trace crap in your water. Think about it. Soap and glycerin. Photo Flo is a final wash/rinse to remove the minerals etc. that comes with tap water from your film. These traces won't hurt you when you drink it (it's bacteria that bites), but they leave residue on your film when it dries. If you're that concerned...do some homework on your local water supply, and maybe do your final rinse with distilled water.

Most bottled "drinking water" is just tap water in a jug.

Quite a racket that. One could get rich re-packaging water. Many do.

Have fun. Shoot every day.
 
Yeah... I heard that years ago too. Photo flo is cheap enough. I would never put soap on my film. I'm sure a lot of folks do it, but why? Get yourself some photo flo.

I couldn't agree more. Why would you even want to try?
Photo-flo is a wonderful thing, but there was also life before Photo-flo. It ws called proper washing and a prayer.
 
Wow, and to think I was a part of it. :king:
 
I kind of miss old Hertz and ksmattfish.

I sort of know where Hertz went (off to take up curmudgeonry full time -but in a good way :)) but have no idea about ks. Anybody else know?
 
Old as hell thread or not, photo-flo is so cheap, why you you even try to make some half-assed version with dish washing soap or something?

If you factor in how long a bottle lasts, photo-flo is probably actually cheaper than whatever the stuff you make with soap would be called.
 
I kind of miss old Hertz and ksmattfish.

I sort of know where Hertz went (off to take up curmudgeonry full time -but in a good way :)) but have no idea about ks. Anybody else know?
Hertz posts regularly over at my little forum; I don't know where else he posts these days. Matt is a member there too, but I've not seen Matt there (or anywhere) for awhile now. Last I knew, he was still a busy working photog in Kansas. :thumbup:

And I still agree with Hertz and the others: with such an inexpensive product available that works perfectly, it surprises me that these questions still circle around. There are other ways to cut costs with the hobby.
 

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