Astronomical Binocular Buying Review Guide

Telescopes aren’t the only viewing tool at the amateur astonomer’s disposal. In part one of a series, I’ll discuss how binoculars can be very useful for several reasons: they are relatively inexpensive, have a large field of view and show images right side up (which makes finding things in the sky easier), are easily portable and require little to no setup.

So, how do you choose a good pair of binoculars for amateur astronomy?

There are different ways of categorising binoculars. Usually, they are distinguished by their magnification and the size of the aperture. A combination of a small magnification and large lens produces a brighter view. A 7×50 pair, for example, gives a brighter image than a 10 x 50, but the image magnification is smaller. A standard 7 x 50 pair is considered one of the best all-round binoculars for practicality, performance and price. For high-powered observation, a magnification of 25x with a 100mm objective lens is recommended.

Observation binoculars come with either straight or angled eyepieces. The benefit of the angled design, usually 45º, is the ease of use and comfort of viewing. The angled eyepiece model is much more user-friendly, allowing more flexibility for people of different heights to use the binoculars without the need to continually adjust the tripod. It is also of benefit when the binocular is trained on the night sky. The straight eyepiece design model will require a higher adjustment of the tripod for each user and this may make the tripod less stable.

If you are forced to go out to the country where you cannot fix your binoculars to something, then consider image stabilised binoculars. These are far more expensive but have other applications as well.

Stabilisation may be enabled or disabled by the user as required. Stabilisation will allow binoculars up to 20× to be hand-held. Major brands making image stabilised binoculars include are Canon, Nikon, and Bushnell.

When I continue with Part 2 of my Astronomical Binocular Review Guide, I’ll talk about various features to look for in a binocular, including digital binoculars.