practicals - wet plates

Monday 19th November - wet plates.  A day spent being taught the Wet-collodion process. 

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The early photographic practice Wet-collodion process, also known as collodion process, was invented  by Englishman Frederick Scott Archer in 1851. The development included adding a soluble iodide to a solution of collodion (cellulose nitrate) and covering a glass or tin plate with the mixture. The plate is then immersed in a solution of Silver Nitrate to sensitise it, after which it is taken out  (in the dark!) and placed in a plate holder, ready for exposure in the camera.

Due to a very low ISO value the exposure time can be anywhere between a second to 20 seconds. After exposure the plate is taken back into  the darkroom where developer is poured over the plate. The development is stopped with water, after which it is placed in a bath of fixer (Sodium Thiosulphate or similar) and then washed and dried.

The low ISO value gives the images a beautiful tonal contrast, but the process is extremely fiddly, with plenty of room for errors!