Brown spots on B&W white prints

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I am a very amature B&W printer and have taken a few classes and now have set up a darkroom in my house. I made a bunch of prints the other day and they came out wonderful except when I hold them up to the light there are brown spots all over them. You do not notice them without the light behind them. What would be the cause?

Help

-- Sheila Masselli (massells@fraserpapers.com), July 23, 2001

Answers

I'm not a printing guru but it sounds like you didn't have them in the fixer long enough or you didn't wash them long enough.

-- Johnny Motown (johnny.motown@att.net), July 23, 2001.

Make sure your hands are clean and chemical free when you take prints out of the wash. Don't rinse off trays near drying prints. These are problems I've experienced before. Once a print is washed it must be kept clean.

-- Tim Brown (brownt@flash.net), July 23, 2001.

What fixer did you use for how long? How fresh was it?

Other two mentioned possible problems but I think those problems take time to become apparent or entire image deteriorate at a similar rate rather than forming spots.

My speculation is that the stop bath and/or fixer weren't fresh and developing agents carried over to such stages caused weak stain. The stain is often clearly visible, but it could be weak. Easy solution may be to use fresh chemicals, and make sure to stop each print for several seconds.

Buffered stop bath (those typically contain BOTH acetic acid and sodium acetate) is usually safe to mix a few times stronger than recommended and they work fast and last long. This frees me from trouble of checking stop bath's pH often.

If the fixer is old but hasn't reached its capacity, it may be helpful to add up to 20g/liter of sodium sulfite, but you might not want to bother unless you have sodium sulfite handy.

Finally, make sure you wash prints well, using clean rust-free water and apparatus.

-- Ryuji Suzuki (rsuzuki@rs.cncdsl.com), July 24, 2001.


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