Jean-David Beyer wrote:
>> I have been reading about divided developers for film.  Never tried it;
>> looks promising though!  Do any of you in this group have any experience
>> with this approach?  The reason for my interest is the fact that i live
>> in the country and that my house disposes of waste water via a septic
>> tank system.  Hence, i want to minimise the amounts of photographic
>> chemicals entering the tank in case they kill the microbes.
> I used several divided developers in the past for 4147 Plus-X and 4164
> Tri-X. I used D-23 or D-25 for Bath 1 and a solution of 2% Sodium MetaBorate
> and 2% Sodium Sulfite for Bath 2. I used up to 7 minutes in bath 1 and 3
> minutes in bath 2.

> The good part was the measured film speed went up one stop.

> The bad part is that it worked the opposite of what people said. They said
> it would lower the highlight contrast while maintaining the contrast
> elsewhere. What I got was that it lowered the shadow contrast (even though
> it increased the film speed). The only way to control the highlight contrast
> was to reduce the time in bath 1, and that lowered the contrast everywhere.

> When I switched films to the TMax series, it was even worse because all the
> sulfite made the sharpness very mushy. So I gave it up entirely.