The process required great skill and included the following steps:
- Clean the glass plate (extremely well)
- In the light, pour „salted” (iodide, bromide) collodion onto the glass plate, tilting it so it reaches each corner. The excess is poured back into the bottle.
- Take the plate into a darkroom or orange tent (the plate is sensitive only to blue light) and immerse the plate in a silver nitrate sensitising bath (for 3–5 minutes)
- Lift the plate out of the bath, drain and wipe the back, load it into a plate holder and protect from light with a dark slide.
- Load the plate holder into the camera, withdraw the dark slide and expose the plate (can range from less than a second to several minutes)
- Develop the plate (using a ferrous sulfate based developer)
- Fix the plate (with potassium cyanide or sodium thiosulfate)
All of this was done in a matter of minutes, and some of the steps in (red) safelight conditions, which meant that the photographer had to carry the chemicals and a portable darkroom with him wherever he went. After these steps the plate needed rinsing in fresh water. Finally, the plate was dried and varnished using a varnish made from sandarac, alcohol and lavender oil.
Dark tents to be used outdoors consisted of a small tent that was tied around the photographer’s waist. Otherwise a wheelbarrow or a horse and covered wagon were used.”