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Old February 7th 04, 08:42 PM
Ken Hart
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Default White spots on negs


"Robert Feinman" wrote in message
...
In article ,
says...
I've read pretty mch everything I can find to get rid of the tiny
white spots on my b&w negs but nothing seems to help. They are only
visible in prints or scans from the negs.

I live in a very hard water area so I'm assuming it's particles in the
water causing it. For my lastest attempt, I used distilled water in
the final rinse and tap water for everything else (ilford say not to
mix chemicals with distilled water) and there was no improvement at
all. This leads me to believe the particles in the water are stopping
development under them rather than drying in the wet film. Should I
try distilled water for everything? Filtered water?

The darkroom I use (the universities) has a "not drinking water" sign
over the sink. Dunno if this means anything.

This problem is driving me nuts! The negs are perfect otherwise. Any
help appreciated.

Can you add a filter to the tap you use?
It sounds like particles in the water. If you reuse your developer there
can also be bits of stuff such as silver deposits and emulsion debris.
Try using all chemicals once (except maybe the fixer).
I don't see why you can't use distilled water for mixing your chemicals.
If something in regular water was required for the formula to work
properly they would add it. Perhaps they are worried about deionized
water which is sometimes confused with distilled. This replaces calcium
salts with sodium or potassium salts. Calgon is a well-known brand. That
might affect the formula.


In my last darkroom, the first negs I processed had tiny "grit" all over
them. If I looked at them with the light at a shallow angle, I could see the
tiny surface particles; which resulted in white spots on the prints.
I got a faucet mounted filter, and that cleared everything up. Later, I had
problems with the water heater (insufficient hot water), and found that the
water heater was filled with calcium/lime (?) sediment up to the bottom
heater element.
When I built my present darkroom (same water company), I installed a whole
house water filter on the incoming line. I also have filters on the water
tempering panels.

Since you are not using your own darkroom, and the faucets are marked not
for drinking, check to see if anyone else has the same problem, and what are
they doing about it. Possibly you might consider one of those water pitchers
with the built-in filter.

Ken Hart