Phenidone as powder expired date?

[Varakan Ten Tipprapa]

Hey everyone

I use Phenidone as powder for Kodak films, but seem the film came out thinner than it should be 2 stop.. I’m afraid that the chemical might ran out date.

Can anyone please answer me how long can I keep Phenidone as powder? And how do you know when it ran out date from outside (if don't have and expired date)

Thank you
Varakan.

[Merg Ross]

Varakan,

I am not a chemist but my 10 year old Phenidone still yields good results. Perhaps there are other variables causing the thin negatives.

[Salty]

I have some phenidone that expired in 1968, it's dark brown but still works. I'll use it in paper developers or Gainer's formulations and it works just fine.