optical zoom = ?mm

[strikeback4]

Hi All

any1 has a link of a chart where like 10x optical zoom is = how many mm?

any1 know, i rmb some1 say 55mm = 3x optical zoom, is it true?

please note the above mm is base on an aps-c sensor camera...

 

[boonsong]

the ?x system refers to the maximum focal length/minimum focal length available in the lens offer.
for instance, if your lens gives a maximum focal length of 180mm, and its minimum focal length is 18mm, then it is a 10x zoom.

what is more important is what focal length that the lens starts with....

 

[Rashkae]

Nope. No link at all.

The "x times zoom" is a marketing brainwash. It is LITERALLY the longest focal length divided by the shortest.

In other words:

A 10-20mm lens is a "2x" zoom. So is a 200-400mm lens. So is a 300-600mm lens, etc etc. A Prime lens will be a "1x zoom", but that prime lens could be 35mm or 500mm.

If you take 2 compact cameras and both say "15x zoom" but one camera starts at 24mm equiv while the other starts at 35mm equiv for wide-angle, you'll end up with the first camera being 360mm at "15x zoom" and the second one at 525mm.

Therefore you really can't compare/translate like that.

 

[strikeback4]

oic, thanks alot for the info...