Different Types of Telescopes

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If you’re new to astronomy, it’s critical to understand that there exist many types of telescopes – and it is important to take your time to explore the purpose each one serves before you dive in deeper.

Most telescopes come into one of 3 categories: refractors (such as using lenses to focus light), reflectors (which use mirrors to focus light), and catadioptric or composite scopes (which use a combination of both lenses and mirrors).

While additional terminology for telescope types, such as “Dobsonian” or “Schmidt-Cassegrain,” maybe referenced, most of the other kinds are essentially variations of the fundamental three, such as a Dobsonian being a form of reflectors or a Schmidt-Cassegrain becoming catadioptric.

Suppose you are a novice seeking to buy your first telescope. Click here to learn What is Quagi Antenna?

In that case, it is advised that you do have a strong vision of just what you need to use it for (visual, photographic, planetary, deep-sky, etc.), your accessible money, and the amount of sophistication you want to take on for your instrument set-up.

The primary purpose of any astronomy telescope is to collect light. Check out What is a Screwdriver Antenna?

People frequently emphasize the telescope’s magnification, which is less essential than the instrument’s ability to catch more light than the observer’s naked eye.

When selecting a telescope, there are several things to consider, but undoubtedly the two most significant are your preferred focal length and aperture.


To concentrate light into a picture, refractors use specially constructed lenses. Open this link to learn What is Squelch?

They are generally lengthy compared to their size because light must travel in a straight line through the telescope tube to the eyepiece.

The lengthier the optical tube of a refracting telescope, the bigger the optics in the telescope. Learn What Frequency Do I Use in 70 Centimeters? By clicking on the link.

Because of the length and diameter of a refractor’s lens and the fact that big lenses may be complicated and expensive for skilled artisans to construct at excellent caliber, larger refractors can be quite costly.

Because most refractors in the industry are smaller than other varieties, refracting telescopes are among the most accessible kinds of telescopes on the street.

You may notice obvious color banding at high resolutions due to the type of lenses used in the optics. Color fringing, also called spherical aberration, occurs when different colored light waves are separated and reach multiple angles, resulting in a picture with unique color at the margins.

Most low-cost refractors are “doublets,” which may exhibit color fringing, but “triplet” refractors are engineered to avoid this problem.

Still, whether it’s a doublet or triplet, their non-movable lenses result in a durable construction that requires little care further than the regular cleaning.


Reflectors employ mirrors to induce light to bounce at different angles inside the optical tube, increasing the overall light path.

Reflectors are usually shorter than refractors with the same aperture because light does not have to travel in a straight line to traverse the same length.

When paired with the fact that making huge mirrors is usually cheaper than producing high lenses, reflectors are often substantially less costly than refractors at greater apertures.

Furthermore, reflectors do not suffer from color fringing in the same manner as double refractors do. Check out this link to learn about Band Plan Frequency Limits

Reflectors are an excellent choice if you want to get the most bang for your income in the form of aperture.

This is particularly true with Dobsonians, including their own simple rocker-box mount. Reflectors may be a terrific buy with several benefits.

They may also be fairly huge and come in a range of sizes. Check out What Frequency Should Be Used on 2 Meters?

Keeping this in view, acquiring the biggest reflector you can buy is an excellent low-cost option to obtain a high-aperture scope. Just be sure you can properly store and carry it.

There are a few factors to consider while designing a reflector. By default, the picture seen via the lens of a reflector is upside down.

As a result, before gazing through the eyepiece, use your scope’s rangefinder to align it with the items you wish to observe.Most new reflecting telescopes come to include a finder lens or a red dot finder, so you won’t need to buy one separately.

Furthermore, a reflector may require collimation, which is the act of adjusting the reflector’s mirrors to ensure they remain in appropriate alignment with one other.

A big reflector, when properly maintained, is a terrific method to observe tiny or distant things with exceptional clarity, and it is an excellent value for obtaining high-aperture vision.


Catadioptrics blend the optical advantages of lenses and mirrors into a tiny, compact container that is smaller and more mobile than refractors or reflectors with the same aperture.

This is facilitated by the prediction plate, which bends the optical path, and the curved secondary mirror, which internally amplifies the light.

This layout has several modifications, including Schmidt-Cassegrains and Maksutov-Cassegrains. Click the link for Single Sideband on 2 Meters: The Other VHF Mode

A catadioptric scope will need collimation because it employs mirrors the same way a reflector does. Nevertheless, unlike reflectors, this technique is far less usually required. A well-maintained compound scope may last for years without needing collimation.

Catadioptrics’ tiny size and portability provide convenience not available in reflectors with the same class, making it an excellent purchase for both novice and expert astronomers.