Shelf Life of Ilford Microphen

While cleaning out the garage today I found an unopened box of

Microphen powder. I believe I bought it about two years ago from a

store that was going out of business, so I can honestly say I have no

idea how old it is. What is the shelf life of powder concentrate?

And what is the useful shelf life of the mixed developer stored in a

closed dark container once I mix it up.

Thanks,

Brian

There are two very different opinions about shelf life of phenidone. My opinion is to verify the usability by dipping in a small piece of film in room light, and see if it darkens in 1-3 minutes. If it does, process a test roll to see if you get normal contrast.

Since Microphen comes in sealed plastic in a box, I think the chance of degradation due to moisture is small. Oxidation should not be a major problem in dry form.

Once mixed, the stock solution should be stored in bottles (glass or certain kinds of gas-tight plastic material) at room temperature. Still,

phenidone is subject to slow degradation even in absence of oxygen. However, Microphen's shelf life should be longer than phenidone-based print developers and even FX-37 film developer because Microphen's pH is much lower, and this deterioration is slower if pH and temperature are lowered.

Thanks,

I did what you suggested, and it turned out great. I did a test roll of Tmax 100 shot at iso 80 for 6 mins at 21c. Turned out great. Just finished up a roll I found from my last trip to NY. Everything looks good. It is a totally different look from the negs I get from Hc110 (the soup I usually use) I'll have to see how they print up tomorrow evening. Thanks again.

Brian