Glossary
Stop
A doubling or halving of light. The unit of exposure.
Open the aperture by one stop and twice as much light reaches the film. Close it by one stop and half does. Same for shutter (1/60 to 1/30 is one stop) and for ISO (200 to 400 is one stop). The whole exposure system is built around stops, which is why the app speaks in stops everywhere: compensation, bias, filter factor, all measured in stops.
Where this shows up in the app
1.2
Aperture f/0.95 to f/64 with half/third stops
Pick aperture in full, half, or third stops across the entire practical range.
Viewfinder > Aperture chip, or Equipment tab > Lenses
5.4
How Bellows Extension compensation works
Extra exposure for the light loss when the bellows racks out.
Tools tab > Bellows Extension