Too good to be true.
- Works equally well with the same processing times in a temperature range of 70? to 85?.
- Gains about a full stop of real emulsion speed with most emulsions.
- No Zone or range worries - it is a very compensating developer.
- Minimal agitation
- Fine Grain and high accutance
- It lasts for years and only needs topping up - NOT replenishment
Sounds like the answer to a maiden's prayer. Sadly, I am no maiden so I will never know for sure.
Diafine is a two-bath compensating film developer. Film gets 3 minutes in Solution A with a gentle agitation every minute, then drain (but don't rinse) and give 3 minutes in Solution B with a gentle agitation every minute. Follow this with a one minute wash in running water (NOT STOP BATH) and normal fixing and follow-through. Only variation to this seems to be Fuji Acros which wants 5 minutes in each solution.
During the soak in Solution A the emulsion soaks up the developing agent but essentially nothing else happens. Solution B is the activator agent and sets the developer to working. Given that there is only a given amount of developer in the emulsion, in the highlight areas where there is most developing activity the solution exhausts quickly and stops working while in the shadows activity continues achieving speed and good low value separation.
Diafine is fine for working in daylight tanks but I choose to use a small deep tank set-up so that I can process rolls or sheets. (I include a snap of the darkroom set-up in a laundry alcove at home.)
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