Crop factor calculator

The arithmetic is all here: crop = 43.2666 / sqrt(width² + height²), full frame diagonal in millimetres; equivalent focal = real focal × crop; equivalent f-number = f × crop, which holds both for depth of field and for total light; angle of view = 2 × atan(side / (2 × focal)). Aperture equivalence assumes the same subject and print size; it says nothing about noise, resolution, or stabilisation, and the light-stops figure is an area ratio, not a measurement of any lens. Computed in this tab, nothing uploaded.