My dag’s have a too low contrast. Even if I develop very long the dag’s stay dark and have a low contrast. At the moment I have only one hood with the mercurybox, the iodinebox and brominebox together. Is there a possible contamination in the air in this hood ? I normally do not speak ENGLISH. I hope I explained myself good enough.
Traces of iodine and bromine in the box will erase part of the latent image during the mercury developing procedure.
Nineteenth Century Daguerreotypists sometimes used this procedure to correct for overexposure of a plate.
You really don’t need a box for the iodine and bromine fuming if your boxes are well sealed with a tight fitting ground glass lid. However if you feel you must use the box for fuming, remove the fuming boxes before you put your mercurizer in the box.