[crystaldragon]

Quote:

Originally posted by cracked
why are pictures squared if camera lenses are round? ive just always wondered this. sorry if it sounds like a stupid question.

drew

No such thing as a stupid question!
I used to make a living in photography.

The simple answer is image degradation. In other words as you get to the edge of the image "cone" formed by the lens the image quality becomes unusable. You see the image from the lens is not only round but also slightly curved, similar to the shape of the surface of the lense itself. To capture a usable image only the sharpest section of the image is used.

The rectangular shape of an image / print is loosley based on the "golden mean" a ration that the human eye finds balanced.

The rotation of lenses to focus is purely a mechanical convenience. Look at any of the older cameras that used a bellows, focus is a function of distance between the lense and the film (or sensor) and can be done be a straight line "in and out " movement just as well.

Clear as mud?

JD