Proofing Diafine

[bvy]

I mixed up some Diafine right before Christmas, processed one roll of film, and put it back on the (dark) shelf. Now I'm wanting to do some more with it. Part A is clear, Part B is a little murky/yellowish but still mostly clear. I want to make sure the stuff is still viable before using it. Normally, I'd drop a piece of leader in a conventional developer and watch it go black. Can I do the same here? Soak in A, then B? Or maybe I'm being fussy...

 

[bvy]

Tried it and that worked just fine. In fact, I was surprised at how quickly the leader darkened when dropped into Part B. I filtered Part B just to make me feel better.

I'm constantly intrigued by this developer. Developing at 85F seems to have a significant impact on density versus developing at room temperature (~70F).

 

[Truzi]

I have a gallon mixed up that I've put only about 10 rolls through. It's about three years old and works fine. I do the leader test any "long-life" developer before using it, though.