The Crop Factor Explained: An Animation

Understanding a very confusing concept

By PF Staff in Tutorial Videos on Jan 19, 2015

The ubiquity of DSLR cameras with "cropped sensors" (the APS-C format) has been associated with a great deal of confusion among seasoned photographers and new users alike, especially when shopping for lenses.

If you've ever been confused by focal length conversions between film/full-frame and APS-C, this tutorial is for you!

We believe that the best way to understand the crop factor is to look at it in the most basic way possible.  Forget all that others have told you, as once you understand the core concepts behind it, you'll be able to fill in the rest of the blanks on your own.

Numerous misconceptions about the effects of having a crop sensor have been floating around and we hope that thanks the animation you just saw, you'll be able to spot them and ignore them. 

Rather than trying to convert focal lengths from one format to another, we recommend just looking at the field of view that different focal lengths have on APS-C.  Two different lenses with the same focal length will always have the same field of view on APS-C, even if one of the lenses was originally designed for a larger format.  This is why the 50mm full-frame lens and 50mm crop lens produced the same exact image in the example above.

If you're still a little unclear on this, try watching the animation again without the commentary:

If you understand the basics and are ready to look at the crop factor from a more technical standpoint, check out The Crop Factor Unmasked.