Quote Originally Posted by Loris Medici View Post
Seems like uneven sensitizing to me.
i think so too.
even though i don't have much experience with vandyke, i think i've noticed that the (slight) bleaching action of the fixing bath accentuates these imperfections. i've had marks and blotches appear in the fix too.
i think this is because of an increase in contrast.

maybe toning, a weaker fix or some more generous coating could be of help.