Options to reduce fog...

[Mkillmer]

I recently shot some old HP4 bought in 1981. Originally ISO 400 , I shot the film at ISO 100.
I have limited developers available.
I developed this film in 300ml paRodinal 1+50 + 5ml 1% KBr
10 minutes rotary development on the Jobo.
The Gil. Has come out heavily fogged.
I would like to reduce the fog.
In my cupboard I have:
Rodinal
D76
Caffenol
KBr
Benzotriazole

Any suggestions how to reduce the fog?
KBr has not solved the problem at the current strength.

[IanG]

HP4 was prone to fogging with age it's unlikely there's anything you can do. Try Rodinal at 1+25 that will give you more contrast and increase the bromide to say 20ml 1% solution but I wouldn't expect more than a very slight improvement.

Ian

[Mkillmer]

Hi Ian,
Thanks for your thoughts -
so...
300ml paRodinal 1+25 + 20ml KBr

Does 7 minutes sound good?

[IanG]

It's worth a try.

Ian

[jcoldslabs]

I can't speak to FP4 specifically, but I shoot a lot of expired films from the 1940s and 50s. What's worked best for me is really strong developer at very cold temperatures for as short a development time as you can get away with. This seems to keep fog to a minimum, but doesn't eliminate it entirely. My starting point has been HC-110 1:19 at 45°F for 3-4 minutes in a rotary drum.

Jonathan

[Leigh]

Benzotriazole is designed to reduce fogging.

Do a web search for recommended formulations, added to the developer.

- Leigh