- Mar 23, 2009
- Med. Format RF
Dear all, I made up abatch of stock solutions of PMK pyro about 2 years old. I keep the solution in 2 glass bottles, one full and the other 1/2 full. I am using the 1/2 full bottle first. Recently, I noticed that the negatives that I developed were thin. Then I found that the stock solution A is darker than usual with small precipitates. The other full bottle stock A remains clear (slightly yellow). I tried to develop with the clearer stock A solution and the negative looks fine. I know that the PMK stock solutions have very long shelf life. I would like to know what has happened to my solution. I have been using PMK for almost 10 years and have never seen these before. My last batch that I used was kept for almost 3 years and had no problem. Could this be contamination. In addition, the clear stock A that I have also shows some precipitates. Is this normal?