Skip to content

Refractor VS Reflector Telescopes

The Difference Between Refractor and Reflector Telescopes

Refractor and reflector telescopes are two primary types of telescopes used in astronomy, and they differ in their optical designs and construction. Here are the main differences between refractor and reflector telescopes:

1. Optical Design:

Refractor Telescope: A refractor telescope uses lenses to gather and focus light. It typically consists of an objective lens at the front of the telescope that collects and refracts light, bringing it to a focus at the eyepiece or camera.

Reflector Telescope: A reflector telescope, also known as a reflecting telescope, uses mirrors to gather and focus light. It employs a primary mirror at the bottom of the telescope tube to collect light and reflect it to a secondary mirror, which then redirects the light to the eyepiece or camera.

2. Objective Lens/Mirror:

Refractor Telescope: Refractor telescopes use a precisely ground and polished objective lens made of optical glass. The objective lens is responsible for bending or refracting light to converge at a focal point.

Reflector Telescope: Reflector telescopes use a curved primary mirror made of glass or metal. The primary mirror reflects and focuses incoming light to form an image.

3. Optical Performance:

Refractor Telescope: Refractor telescopes are known for producing crisp and high-contrast images, especially when well-designed and using high-quality lenses. They have minimal optical aberrations, such as chromatic aberration, when apochromatic or ED (Extra-low Dispersion) glass elements are used.

Reflector Telescope: Reflectors can provide excellent image quality as well, particularly for larger aperture sizes. However, they can be prone to some optical aberrations, such as coma and spherical aberration. These can be minimized by using high-quality mirrors and employing corrector lenses or coma correctors.

4. Chromatic Aberration:

Refractor Telescope: One common challenge for refractor telescopes is chromatic aberration, which occurs due to the different refraction of different colors of light. This can cause color fringing around objects, particularly in cheaper refractors. Apochromatic or ED glass elements are often used in higher-end refractors to minimize this issue.

Reflector Telescope: Reflectors are not prone to chromatic aberration since they use mirrors rather than lenses to gather and focus light.

5. Size and Portability:

Refractor Telescope: Refractor telescopes tend to be more compact and lightweight for a given aperture size. They are easier to transport and set up, making them suitable for portable observations.

Reflector Telescope: Reflectors can be larger and bulkier due to the need for a primary mirror. They require a sturdy mount and are less portable. However, smaller reflector telescopes can still be relatively compact and manageable.

6. Cost:

Refractor Telescope: In general, refractor telescopes tend to be more expensive compared to reflector telescopes of similar aperture sizes. The cost is primarily driven by the need for high-quality lenses and their more complex design.

Reflector Telescope: Reflectors are often more affordable for their aperture sizes, making them a popular choice among amateur astronomers.

The choice between a refractor and reflector telescope depends on factors such as budget, desired image quality, portability, and specific observing preferences. Refractors are well-suited for planetary and lunar observations, while reflectors are versatile and excel at deep-sky observations due to their larger apertures.


Visit our Space & Telescope FAQs page for more fun & interesting facts.

Buy a New Telescope today. Our telescopes are the perfect way to see planets, stars, and galaxies up close and personal. They are easy to use and affordable, so you can start exploring the wonders of the night sky.

Back to top