Telescopes Choosing a Telescope

A telescope is a lens system that offers a higher magnification than can normally be obtained in a hand held system.

Choices that have to be made:

Size of the objective lens. There are three general sizes: small – 50/52mm, medium – 60/66mm and large – 80/88mm. The smaller lens gives a lighter weight instrument but trades off light at any given magnification, 60/66mm and 80/88mm offer larger, brighter images but are generally heavier, less portable instruments.

Telescope bodies can be angled or straight, regardless of objective lens size. The straight body is easier to aim and better for use from a hide whereas the angled body is easier to share and can be mounted more steadily on a tripod.

Eyepieces are the element that adjust the magnification. There two main types: fixed wide angle eyepieces (usually 20x up to 30/32x, occasionally going up to 40/45x), which give as near the optimum view as possible, or zoom eyepieces which offer a range of magnifications (usually around 20-60x) by simply rotating the eyepiece. The angle of view is generally reduced and light transmission is diminished as the magnification is increased.

Lenses can be standard glass or ED, FL or HD glass. These latter types improve light transmission and reduce colour fringe (chromatic aberration) but at additional cost as this type of glass is expensive to produce. As always the balance is between cost and performance. Extra cost often equals brighter, sharper images. Above all, it is important to remember that, generally, these instruments cannot be hand held and a tripod or clamp has to considered when purchasing a telescope. We stock the following brands of telescope:

We stock the following brands of telescope: