A synonym for crop factor based on the fact that multiplying a lens’ focal length by the crop factor yields the focal length of a lens that would yield the same field of view if used on the reference format. Focal length multipliers are typically used to convert digital camera and lens combinations to their 35mm equivalent. Most digital cameras have an APS-C size sensor which is smaller than the 35mm film. The smaller sensor size of these digital camera’s results in a multipler of 1.3-2.0x.
Multipliers for popular digital cameras are:
- Nikon DX cameras – 1.5
- Cannon – approximately 1.3x
- Nikon FX and Canon full-frame format cameras – 1.0x