What Is Magnification? - Canon 10 x 30 IS Manual

Magnification refers to the ratio of the size as seen with the
naked eye and size obtained with the binoculars. For example,
if a pair of binoculars has 10x magnification, an object will be
enlarged 10 times. In other words, something 100 meters away
will look 10 meters away through the binoculars.
A car 100 meters
away with the
naked eye.
A car 10 meters
away with the
naked eye.
Magnification and focal length
A 1,000 mm telephoto lens for a camera will provide five times
higher magnification than a 200 mm lens. The same applies
to binoculars, in that an object is enlarged five times more
with 20x magnification binoculars than with 4x magnification
binoculars. The only difference is that, while a telephoto lens
must be wide enough to magnify the image for the fairly
wide aperture of the camera, binoculars need only magnify the
image for the relatively smaller iris of the human eye. Say for
example you have 12x magnification binoculars. To get the
same enlarged image using a 35 mm Single lens reflex camera,
you would need to use a 700~800 mm telephoto lens.
With a 10x magnification binoculars,
a car 100 meters away will seem as
if it were 10 meters away.