This process can also be used to produce images on blackened steel, tin, or aluminum. These images are underexposed negatives that appear as positives. When steel is used they are referred to as ferrotypes, or more commonly know, tintypes. Images on glass are called ambrotypes. The use of modern blackened aluminum is referred to as alumitypes.

The plate (negative) is then put in the camera where it is exposed. Generally exposures run from 2-10 seconds for tintypes and 2-3 times as long for negatives. Once the plate has been exposed it is developed in an acid solution of ferrous sulfate. It is rinsed and then fixed. The entire process must be done while the plate is still wet. If the plate dries out it looses its light sensitive properties. This is why the process has been known as “wet plate photography” or wet plate collodion”.

Wet plate collodion was used up until the 1880 when it was replace by dry plates and eventually film.

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