150 mm Aperture Refractor Telescopes

Choosing The Right Refractor Telescope

There is a lot to capture in the outer space and crisp high-contrast images will definitely enhance your experience. A suitable telescope on your tripod will also work great with your refractor telescope for a worthwhile view of the sky objects.

How does a refractor telescope work?

Refractor comes from the word refraction which basically means bending light through a lens. In astronomy, this is what a refracting telescope does.

The objective glass, also known as the primary mirror, captures the real image and makes it small. This small image is then passed through the eyepiece lens where it is enlarged for you to see when you look through it. 

What should I look for when choosing a refractor telescope?

The market is loaded with all types of telescopes, the likes of Celestron, Skywatcher, and Carejoys astronomical telescope. It is therefore important to know what to look out for when choosing one. Let us look at the factors to put into consideration.

  • Focal length - The quality of an image will be highly affected by the diameter of its optics. The wider the lens, the clearer the image quality. That being said, a 150mm, focal length, refractor telescope will expose a better image than one with a 120mm aperture.
  •  Quality of the glass - If the optical glass is made of poor quality, then you can be assured that your images will be equally bad. It needs to be a perfect sphere for it to work effectively.
  • Angle magnification - The angular magnification of the image matters because it highly affects the clarity of the image you will get. 

What are the advantages of a refractor telescope?

Here are some of the benefits that come with using this type of scope.

  • Long focal ratio - Its wide-field enables you to use longer focus and simpler eyepieces
  • Good optical alignment - Coupled with an easy-to-handle tube, this telescope requires minimum maintenance. Its near-permanent optical alignment gives it a major plus.
  • No reflections - Using refraction, rather than reflection means the refractor does not get light interruptions in its light path.
  • Aperture superior power - It has a superior revolving power for every inch of its aperture. 
  • Steady image - Light pollution obviously degrades the sky and this can limit the quality of your image. This, however, does not affect your images when using this telescope. In that regard, refractor telescopes make an excellent choice for widefield astrophotographers.

Does the refractor have any disadvantages?

There are also some disadvantages that come with using this type of telescope.

  • Having long focal ratios can make this scope cumbersome.
  • You need to constantly collimate the optics.
  • Refractors suffer chromatic aberration which causes color distortion.
  • It is difficult to make a perfect glass with a perfect curvature on both sides.
  • The objective lens can only be supported at its ends, making the glass sag from its weight.