As I’ve worked in the wet plate collodion process, I’ve accumulated many images that show extreme effects of chemical reactions and accidents of the process.  Sometimes colder temperatures caused the developer not to flow properly.  In other instances, the collodion was too old and formed on the plate in a mottled way as it was poured.  Then there were also cases of silver nitrate flowing across the plate and leaving traces of movement while the plate was in the camera holder.  Finally, there were some plates that had contaminants on their surfaces — specks of dust, and such.  These are among my favorites.