Quote Originally Posted by Photo Engineer View Post
Matt, there was a thread on this a while back. There is a good test that relies on the time of development o achieve a given density of fresh and kept developer. Small clips of film are used.

PE
PE:

That is a "good" test, but not necessarily an "easy" test.

The need for the test is most pronounced for those of us who have inconsistent film use needs, and temporary darkrooms - so something that just requires us to put a couple of drops of a solution into a few millilitres of developer and check for precipitate would be wonderful.