Focal Length Equivalent
Match settings between different sensor sizes
How to use Focal Length Equivalent
- 1Enter the actual focal length of your lens.
- 2Enter the camera sensor crop factor (e.g. 1.5 for APS-C).
- 3Read the full-frame equivalent focal length and its angle of view.
What Is a Focal Length Equivalent?
equivalent = focal length × crop factorDifferent sensor sizes capture different fields of view for the same lens. The full-frame equivalent tells you what focal length on a full-frame camera gives the same perspective.
This makes it easy to compare lenses across camera systems and understand how 'zoomed in' a shot will look.
Frequently asked questions
Why does sensor size matter?
Smaller sensors crop the image, effectively magnifying the focal length, so the same lens looks more zoomed in.
What is a crop factor?
It is the ratio of a full-frame sensor's diagonal to your sensor's diagonal; APS-C is about 1.5, Micro Four Thirds about 2.0.
Does equivalent focal length change depth of field?
Perspective stays the same; only the field of view is matched. Depth of field also changes with sensor size at equal framing.