Photography Explained Podcast - What Is Crop Factor?

Crop factor is the number that is used to calculate the effective focal length when taking a photo with a cropped sensor camera or a micro four thirds camera.

A full-frame camera has a crop factor of 1 in theory, a cropped sensor camera has a crop factor of 1.5 - 1.6 and a micro four thirds camera has a crop factor of 2.

The crop factor converts the focal length stated on the lens to the effective focal length, for example

• 50mm on a full-frame camera is 50mm.

• 50mm on a cropped sensor camera is effectively 75-80mm.

• 50mm on a micro four thirds camera is effectively 100mm.

Basically, crop factors relate to the different sizes of digital camera sensors. The term crop factor is very important in photography, we really do need to understand this. This is about the physical size of the sensor, and how this affects the focal length selected and the effective focal length that you get.