This is also just a stab in the dark but if your selenium was mixed fresh perhaps not all of the compound had fully "dissolved". Or indeed, old stock that had "settled out" and needed to be thoroughly mixed again.
I can't substantiate this, but I often have a feeling that chemicals behave differently between let's say fresh vs more recently matured. And certainly for stock solutions from powder, I prefer to mix them 12-24hrs before use.
Again sorry for not being able to comment on Bergger as I use Kodak RST.
__________________
MartyNL
“Reaching a creative state of mind thru positive action
is considered preferable to waiting for inspiration.” - Minor White, 1950
|