The Kodak data sheet for T-MAX concentrate says that it is good for two years. Does this apply after the bottle has been opened or is this for an unopened, full bottle.

To be more specific, my normal way of working is to mix up only as much of the concentrate as I need to develop one or two rolls of film - whatever I happen to have ready to develop at the time. I have a bottle of concentrate that I started to use about two months ago. It is probably more than half full. Is it still good?

thanks, Peter Schauss

-- Peter Schauss (schauss@worldnet.att.net), November 29, 2001

Answers

It's been a while since I used T-Max developer, but I seem to recall keeping an opened bottle for quite some time and never experiencing any problems with it. Kodak's documentation says: "You can store working-strength solution in a full, tightly closed bottle for six months, in a half-filled bottle for two months, or in a covered tank for one month. You can store the concentrate for up to two years." The two year figure is probably for an unopened bottle. If you plan to store the concentrate for any great length of time, I would suggest you obtain several small brown glass bottles and put it in those, with as little air as possible. That should give you maximum shelf life. If your current half-full bottle is only two months old, it should be fine, and if you use the rest in another two months it's not likely you will have any problems with it deteriorating before it is all gone.

-- Ed Buffaloe (edb@unblinkingeye.com), November 29, 2001.

I am not sure about T MAX, but I have used T MAX RS 6 to 8 months after I opened and it still was good. There was a little bit of discoloration but nothing that reflected on the developing properties.

-- Jorge Gasteazoro (jorgegm58@prodigy.net.mx), November 29, 2001.

A technique that I use with liquid concentrated developers is to put in glass marbles to evacuate the air as I use up the liquid. This will likely extend the life of the concentrate. If the bottle becomes less than half empty, I transfer it into a smaller bottle, always keeping the air out with marbles.

-- Michael Feldman (mfeldman@qwest.net), November 29, 2001.

With both T-Max developer (which I'm hardly using any of these days) and Polymax T paper developer, Kodak packages in the same plastic bottle. One can easily squeeze the bottle sufficiently when closing to eliminate air while up to half the contents have already been poured out. This should mean that Kodak's six month rating can be maintained instead of two months for a "half-filled" bottle.

-- Sal Santamaura (santamaura@earthlink.net), November 30, 2001.