Negatives produced by the dry collodion process, comprising several types developed between the mid-1850s and 1860s. These negatives were based on the same process as wet collodion negatives, but allowed for the plates to be prepared in advance, by adding a surface coating to the sensitized plates that kept the surface moist, extending the time between preparation and exposure. These plates required far longer exposure times and proved less popular that wet collodion negatives.
