Canon 10 x 30 IS Technology Guide - Page 6

Q3 What Is Magnification? 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. With a 10x magnification binoculars, a car 100 meters away will seem as if it were 10 meters away. 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. 6