MAGNIFICATION
EXPLAINED
A Binocular will usually be marked so that you know what to expect from it. Typical specifications are 8 X 20,  8 x 30, 8 x 40 or 10 x 50. 

The first figure indicates the degree of magnification and the second, the diameter of the objective lenses, in millimetres. For most purposes, magnifications of between 6.5 x and 10 x will be most satisfactory. As magnification increases, the size of what you look at will appear larger, but any slight hand movements will also be exaggerated so that you may not be able to keep the binocular steady enough also, focusing will need to be more precise and the field of view may become narrower. The diameter of the objective lenses will control how much light the binocular can collect. In bright conditions the lens size will not be too important, but larger lenses will be able to maintain the brightness of the image even in poor lighting. Usually the greater the number of times that the magnification can be divided into the objective lens diameter, the brighter the image will be

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