How to Choose a Spotting Scope

If you are thinking of buying a spotting scope it is important to take into account the uses you plan for the instrument. Knowing how it is likely to be used will narrow down the range to choose from.

They can be used for many purposes such as long distance sports viewing e.g. boat races, nature observation, surveillance as well as just enjoying a nice view.

Just as with traditional telescopes, the quality of the spotting scope's image depends in part on the aperture of the objective (front) lens. The larger that aperture, the more light the scope can capture so the resulting image will be brighter and sharper.

Magnification is determined by the focal lengths of both the scope itself and the eyepiece used with it. Spotting scopes might be designed to provide magnifications of say 15x to 60x depending on the eyepieces used. Many modern spotting scopes are fitted with zoom eyepieces so there is no need to change eyepieces or to carry different eyepieces around.

Bushnell Trophy 20-60x65 Waterproof Spotting Scope (Green)

Celestron 52250 80mm Ultima Zoom Spotting Scope

Swarovski Spotting Scope HD-ATS 80 High Definition

Celestron 52251 Ultima 80ED Zoom Spotting Scope

Models with their eyepiece angled at 45 degrees help with comfort of the viewer and can more easily be used by people of different heights without resetting the tripod. Spotting scopes should always be used on a tripod or with some other support as handheld use is impractical due to the handshake effect.

If you plan on spending a lot of time in the wild it would be a good idea to look for a lightweight model which has some waterproofing and body armour like the Bushnell Trophy above. If you will be using the scope in dim light like birdwatchers often do then a large aperture lens will help with performance.

If very high quality of image is important then perhaps consider models with fixed focus eyepieces rather than the zoom models. Extra low dispersion (ED) glass might also be worth thinking about, this is a special type of glass which minimises the dispersion of the different wavelengths of light and gives a very sharp image.

For photography, a catadioptric spotting scope is often preferable to the prism types as the absence of internal prisms with shorter focal lengths and faster focal ratios tends to give sharper photos.