what is optical zoom?

Answer 1

Optical zoom is where the camera lens zooms in and out enlarging or decreasing the size of picture so that you can zoom in and take a picture of the zoomed image, digital zoom is where you enlarge the picture via software by simply enlarging the pixels. The two are distinctly different.

Answer 2

An optical zoom lens changes its focal length as it zooms but still uses all the pixels on its sensor so maintaining the quality of the image. Not only do you 'get nearer' to the subject but also the perspective changes. A short focal length makes distant objects smaller relative to the nearer ones and vice versa. We are so used to a single focal length eye (!) that we can be deceived by these changes. Difficult to explain here, sorry!
A digital zoom reduces the number of pixels it uses on its sensor to those nearest the centre so the picture quality becomes worse. The perspective does not change.You get the same effect by cropping the picture on the computer so basically it is worthless except as an advertising gimmick.
RoyS

Answer 3

In an optical zoom, the lens elements (or someof them) move. A digital zoom merely uses the camera software to enlarge a portion of the picture. A digital zoom is useless, and only leads to picture degradation - you could, just as easily, and probably more effectively, crop the picture in an image editing program and enlarge the part you want.

Answer 4

There are many possible designs for zoom lenses, the most complex ones having upwards of thirty individual lens elements, and multiple moving parts. Most however follow the same basic design. Generally they consist of a number of individual lenses that may be either fixed, or slide axially along the body of the lens. As the magnification of a zoom lens changes, it is necessary to compensate for any movement of the focal plane to keep the focussed image sharp. This compensation may be done by mechanical means (moving the complete lens assembly as the magnification of the lens changes), or optically (arranging the position focal plane to vary as little as possible as the lens is zoomed). Some early zoom lenses, referred to as varifocal lenses, did not preserve focus as the zoom setting was changed. This simplified the lens design, but required the user to re-focus the lens after zooming.

A simple scheme for a zoom lens divides the assembly into two parts: a focussing lens similar to a standard, fixed-focal-length photographic lens, preceded by an afocal zoom system, an arrangement of fixed and movable lens elements that does not focus the light, but alters the size of a beam of light travelling through it, and thus the overall magnification of the lens system.

Answer 5

You get optical & digital zoom on a digital camera. if you have 3X optical & 4X digital you multiply the numbers so 3X4 means 12X altogether. Using only the optical zoom gives better quality prints but if you use the digital zoom too then you will get the detail but a grainier print. Hope this helps you. Merry xmas

Answer 6

Magnification using lenses as opposed to digital zoom which uses logarithms to increase the size of an image. Optical is more accurate as digital uses a best guess at what colour adjacent pixels should be, not always successfully.

Answer 7

Zooming using lens, they use this term to differentate it from 'digital zoom' that is often used by digital camera.

'Digital zoom' is zooming using software.

Answer 8

zoom supported by the camera lens

Answer 9

This allows the picture to be moved in closer or at a further away distance

Answer 10

same as any other zoom but better graffix