The gelatin POP process was often used in commercial portraiture at the end of the 19th century. Most gelatin POPs were produced on cabinet card supports. The POP process involves contact-printing a negative onto paper using a light source. This process met consumer demand for newer small-format cameras as well as existing large-format cameras. POP allowed for exposure using gaslight, kerosene lamps, or electrical lightbulbs and for exposure to be monitored while an image gradually appeared.
The gelatin POP process was often used in commercial portraiture at the end of the 19th century. Most gelatin POPs were produced on cabinet card supports. The POP process involves contact-printing a negative onto paper using a light source. This process met consumer demand for newer small-format cameras as well as existing large-format cameras. POP allowed for exposure using gaslight, kerosene lamps, or electrical lightbulbs and for exposure to be monitored while an image gradually appeared.