Why do bigger camera censors have more natural blur?



Why do bigger camera censors have more natural blur?

In: Technology

It’s more that there is a wider variety of lenses available on cameras that have large sensors, in particular lenses with large holes (apertures).

Lenses with a large hole give the rays of light more opportunity to stray off course before they are focussed back onto the sensor. The stuff that isn’t focussed is what causes the blur, ie they’ve got jumbled up with all the other rays of light.

A small hole means all the rays of light go straight through and hit the sensor without much opportunity to mix and cause blur.

Cameras with large sensors let you use lenses with a longer focal length to get the same field of view. A wide angle lens on a phone might have a focal length of around a mm, on a full frame camera it’s more like 14mm. At a given focal ratio (f/1.8 is common on phones and camera lenses) this longer lens will have a larger aperture, this larger aperture lets in light from more angles which results in a shallower plane of focus, effectively the natural blur you are talking about is due to the area which is in focus being smaller.

You could theoretically get the same effect by using a ridiculously low f/ ratio on the phone camera, but in practice anything below f/1 is incredibly difficult and you’d have physical constraints on the width of the lens as well.