Storing Long Term Chemicals

photoman · Apr 12, 2004

Hi ive been reading on the storage lives of chemicals and found that they would last the longest if they are stored full in a container so that they wouldnt oxidize. Ive been using some of the blatters you would find in box wine (as you use them they still remain full because they dont let air in). I have been using them for about 3 months now with no problem for long storage of chemicals like dektol and D-76.

My question is would there be a problem in the wine that was previously in them affecting the chemical working ability or storage life?

I would also like to know what everyone else does about storing their chemicals (anybody else have some neat way of storing them

).

Any advice would be helpful

ksmattfish · Apr 12, 2004

I would worry about the wine, unless you are sure they are completely washed out.

You can buy several different kinds of collapsing containers for chemical storage. The best way to store chems for long periods is in powder form. With a small scale you could mix to use, instead of mixing up the entire package.

Another trick I've heard of is to pour glass marbles into the containers as they are emptied.

jrgoresko · Apr 26, 2004

When information for shelf life of a chemical is being given, is it under the assumption that the chemicals are simply being stored in a plastic container? I've just been using (I think they're a gallon) jugs that I had left over from school.

ksmattfish · Apr 26, 2004

I think that the assumption is that they are being stored in an airtight container with a minimum of air chemical contact.

Film developer: no way to know if it's gone bad until it wrecks your film, so don't take chances here. Always use fresh chems if possible. Develop lot's of film at once to completely use up film developer.

Print developer: weak paper dev will keep you from getting solid blacks. I keep using paper dev until this shows up, as I only lose an easy replacable work print, and I get the most for my money out of the chems.

Stop Bath: you can use an indicator stop bath which shows when it is depleted. Even if stop goes bad, many photogs don't even use stop, they just use a water bath. So with stop bath it's not as important, although I think it's very easy to mix up a weak one session use batch each time.

Fixer: if your fix for film is weak, and your film doesn't clear all the way, then you can always re-fix. So you can use questionable fix on your film. For prints you won't have anyway of knowing until the print is ruined over time, so always use fresh fix for your prints, and save the older stuff for film.

jrgoresko · Apr 26, 2004

About film developer, I read that I can keep a half-full, airtight container for 2 months. As long as I stick to this I'm fine aren't I? Do you really mix a whole gallon and then use it all right away? Or do you use liquid chemicals and mix smaller amounts to suit the number of rolls you're processing? I need to make my photographic ventures somewhat economical, so I plan on continuing to use powder chemicals unless someone gives me a logical reason not to? Do you have any preferences regarding powder vs. liquid? Why/why not?

ksmattfish · Apr 26, 2004

I prefer concentrated liquid chems because it is easy to mix up a one shot batch, but I also use the powders for more economy. A gallon of dev won't sit around my darkroom for very long because I shoot at least two or three rolls (roll = 80 square inches) of film a week in a slow week, and a lot more on a busy week. And I save up film and develop it all at once every month or so.

I have a developing tank that holds 2.5 gallons of chems and processes 18 rolls of 120 size film at once (more than two times that many rolls of 35mm). Pretty obnoxious, but I have actually used it once or twice.

Normally I use a tank that holds 64oz of chems, and 4 120 reels or 8 35mm reels. Although to insure good chem mixing I only load up 3 of the 120 reels or 5 35mm reels and use about 44 oz of chems (just enough to insure that all the film is covered if I let the tank sit). The extra space helps mix up exhausted developer with the fresh stuff. Right now I'm using Sprint liquid film dev and 44 oz is good for about 6 rolls.