Bergger Berspeed is a high-energy, fine-grain film developer for black and white negative films. This powdered developer should be mixed to make 5L of stock solution, which can be used straight or mixed at 1:1 to make 10L of working solution. It is well-suited for use with high-speed films, including those with tabular grain emulsions, and delivers full film speed with full shadow and highlight detail. When stored in a dark, airtight container, stock solution has a shelf-life of approximately four months