Digital BW, The Print

Sorry I didn't get to this earlier.  Clear spots in the film mean too much
acid in the stop bath, because it causes gassing in the subbing.  Dark spots
mean either not enough acid in the stop, or exhausted stop, or contamination
caused by trace amounts of developer still present on the film when it
arrives in the fixer.  If there is a brown ring around the stain, that would
be proof enough for me.  The best book on the subject is STAINS ON NEGATIVES
AND PRINTS published by Kodak (now out of print).  In twenty years, neither
EK or Ilford rapid fix have caused this problem in my darkroom, because I
use separate tanks for each chemical.  One thing more to lookout for if you
use Tmax developer is be sure you get all the photoflo off your reel and
tank perfectly first or you may experience splotchy development.

Tom Robinson

>> Thanks Martin,
>> 
>> In fact, I did spot one last night and got to the point in about a
>> half hour where the damage was not obvious in the print.  Will try
>> again, using more care at the end of the wash cycle.  I did switch
>> from Kodak to Ilford Rapid Fix and I wonder if it was either a bad
>> batch or the Ilford requires a longer wash than the Kodak.  I usually
>> wash for seven to eight minutes after using a hypo clearing agent.
>> 
> Steve,
> 
> I've used Ilford Rapid Fix for years and the problem comes and goes. As
> someone else mentioned it is very likely the hardness of the wash water
> which would not be constant. Our water here is well water with a high
> mineral content.
> 
> Martin