I've not done any pt/pd prints since the fall. I've been trying to do test strips today, and my exposure times are getting up to 16-20 minutes and they still look lousy. My usual times with my tanning lights are in the 3-8 minute range. I'm using Na2 method. Bought the chemicals in solution from B&S. I think my ferric oxalate solution is from last summer. It might be older. It has been kept in the fridge when not in use. Is it just too old? I think I've read that the other solutions will keep forever, but the ferric oxalate expires eventually.