photolytic wrote:Daguerreotype plates thus polished react more rapidly to iodine fumes producing a thicker coating. It may be necessary to reduce the fuming time in order to bring the contrast back up to the desired level.

This is very true. The sensitivity increases as well but you do lose contrast. Double-edged sword, really. Sometimes I’ll lay down a heavy Iodine layer if I know that I’ll need a (comparatively) fast exposure.