Refractor Telescopes

Refractor Telescope

The majority of refractor telescopes use two lenses of different sizes. The larger objective lens is what focuses the light down the telescope’s tube, in order for the second lens, the eyepiece lens, to receive it. You’ll see objective lenses described in terms of their diameter, expressed in millimetres (mm). The larger an objective lens, the clearer and brighter the image it produces. However, a physically larger lens requires a longer tube to focus light through, meaning the telescope as a whole is larger, and heavier too. For this reason, refractor telescopes often tend to have a narrower diameter than reflector telescope, making them lighter, but meaning they take in less light.

Refractor telescopes are known for providing an image with excellent sharpness and contrast. For this reason, they are excellent deep-space telescopes, ideally suited to viewing some of the most distant objects in the night sky. If you’re looking for a telescope for watching galaxies, a refractor is definitely the best choice. Whereas if you’re more interested in viewing the moon and other objects closer to home, you may be better off with a reflector telescope.

Unlike reflector telescopes, refractors don’t require regular collimation (alignment of the internal components) in order to perform at their best. In fact, they are generally very low-maintenance, since their components are completely isolated in a closed system, protecting them from exposure to dust and humidity.

The lenses can suffer from chromatic aberration – a form of colour fringing that can cause discoloration at the edges of objects. To counteract this, some refractor telescopes add in an extra lens – these are referred to as ‘apochromatic’ (which isn’t the same thing as ‘achromatic’, a term used to refer to telescopes with two lenses).

Refractor telescopes have all sorts of advantages. The more sophisticated apochromatic examples tend to be favoured for astrotography over reflectors, as they produce a clearer image that’s great for producing vivid photographs of distant objects. The simpler, cheaper achromatic models are also popular among astronomy beginners, as they don’t require too much maintenance or calibration. At Wex we offer a broad selection of these types of scopes from all the major manufacturers, with Celestron and Skywatcher refractor telescopes at a range of price points. Whether you’re a total novice or a seasoned observer, we’ll have the right telescope for you.