Unless they are from fixer being splashed onto something, they would be defects on a print resulting from fixer that was not washed off during the developing process.
fixer
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In Fixer you can find Sodium thiosulfate :Na2S2O3·5H2O and Ammonium thiosulfate: (NH4)2S2O3 for black and white photography, in purpose to remove unexposed silver halide.They can not be found in developer ! In Developer for black and white photography: Metol,Phenidone and Hidroquinone for purpose chemical that makes the latent image on the film or print visible!
Sodium thiosulfate is not a base; it is a neutral compound with a pH close to 7. It is often used as an antidote for cyanide poisoning and as a fixer in photography.
Fixer Chao was created in 2002.
When your print is developed, is is still prone to be altered by light exposure.thus the fixer alters the chemicals on the surface so that this no longer happens.This is why the working light is red, a colour film does not much respond to.But you can try a very slight exposure before fixing, to get some interesting results! using the enlarger as source.
tail fixer, teeth fixer, tusk fixer, the world is your oyster
click on the social fixer wrench and there will be a number of options available, just click disable social fixer.
The duration of The Fixer Uppers is 1140.0 seconds.
The duration of Fixer Dugan is 1.13 hours.
The duration of Parole Fixer is 1.13 hours.
The duration of The Fixer - film - is 2.2 hours.