 C-mount lenses have been made for many different formats.C-mount lenses are built for the 8 mm and 16 mm film formats and the 1/3", 1/2", 2/3", 1", and 4/3" video formats, which corresponds to a range of image circles approximately from 5 to 22 mm in diameter.Depending on the format, the design of the lens and its performance will differ considerably.