Why Depth of Field is NOT Effected by Sensor Size – A Demonstration

This is probably one of the most argued about topics in digital photography. For as long as we can remember people have been arguing that if you will use a camera with a larger sensor (with the same lens and same settings) you will get more depth of field (DOF) or basically better separation between your subject and its background.

Well, in this video from 2012, photographer Matt Granger (aka ThatNikonGuy) set out to disprove this claim once and for all. He used the Canon 1D-X with a Full Frame sensor and the tiny EOS-M (with its APS-C sensor) along with the same 70-200mm F/2.8 lens in exactly the same settings to shoot an object with a clear second object in the background.

Sensor Sizes in different cameras (the relative size of the sensors in the table is done to scale)

Sensors size-01-01

The resulting DOF was a clearly identical (although the EOS-M image was of course cropped due to the smaller sensor). Interestingly from the reaction to the video – lots of people continue to claim that DOF is in one way or another dependent on the sensor size…

At the end of the day, besides not having your image cropped, larger sensors will give you one clear advantage – and that is having more surface to collect light, and thus better sensitivity (when all other things being equal of course). With today’s technology you can typically expect about 1 stop more light when moving from APS-C size sensor (of a specific manufacturer) to a Full Frame camera of the same manufacturer.

You can find many more great tips on our photography tips section – here on LensVid.