Should You Use An Alt Az Or Equatorial Mount

Should you use an ALT-AZ or Equatorial Mount?

Mounts are an essential unit for your telescope. It can either make or break your astronomical fantasies.

For beginners choosing between a bundle of mounting choices can be frustrating. But your overall pick should fall between the two basic mount types.

The Alt-Az mount and the Equatorial (EQ) mount are the most conventional mounting designs. We have broken down the parameters that will lead to a fulfilling purchase.

A perfect placed choice for a mount can make alignment or tracking hassle-free. But a poor decision can lower your chances of experience quality astronomy.

It is essential to understand the workings and concepts of each variant for a fulfilling purchase. Follow along for a more elaborate insight into the realm of telescope mounts.

What are the different types of mounts?

Mounts for telescopes come in two different varieties. Each has their advantage and disparity. To best choose a mount, you must know about each type comprehensively.

Alt-Az Mount

The Alt-Az mount is the most conventional and straightforward telescope mounting design. The Alt is an acronym for altitude, and Az is short for azimuth.

The altitude axis allows for movement in “up and down” directions. And the Azimuth axis has scope for moving the telescope in “left to right” directions.

There are various sub-categories of Alt-Az mount. Some of these include the Single arm fork mount, Dobsonian mount, dual-arm mounts, etc.

The most striking feature of this mount is simplicity. They are easy to set and install, and future usage is convenient.

Equatorial Mounts

An equatorial or EQ mount is a derivative of the Alt-Az mount. However, both the concepts and functionality of an EQ mount are more complex than an Alt-Az mount.

This mount has two axis of rotation- the Declination (DEC) axis and the Right Ascension (RA) axis. Each axis has a different scope.

The Declination or the DEC axis allows for the scope to move from north to south. The RA or the Right Ascension axis helps conduct east to west movement.

The axis system helps you understand the similarity between an EQ and an Alt-Az mount. The critical difference between the two mounts is the polar alignment.

An EQ mount needs to be polar aligned. In simple terms, when the scope is equatorially mounted, it should be pointing towards the north celestial pole.

The basic principle behind an EQ mount is to cancel the relative of Earth’s rotation. As it moves opposite to the geological rotation, the apparent motion is canceled out.

Why do you need a telescope mount?

The primary purpose behind purchasing a mount for your scope is stability. Without a mount, the most convenient tasks of astronomy seem like a burden.

A telescope mount not only keeps the system safe but also ensures optimal tracking. You can easily adjust the discrepancies caused by the Earth’s rotation.

So, which one should you choose? An EQ mount or an Alt-Az mount?

An Alt-Az mount offers unparalleled simplicity. Astronomers prefer these mounts for terrestrial observations at relatively low powers.

An Alt-Az mount is not ideal for deep sky astrophotography. Because these mounts are so feather-light, they make for portable options when you are on the go.

Due to the Earth’s rotation, you observe the stars are always moving across the sky. If you view such objects with an Alt-Az mounted scope, they will readily drift out of your field of view.

We have mentioned some scenarios down below. If you relate with any, an Alt-Az mount is the best choice for you:

  • You are hesitant about feeling overwhelmed all together by buying a sophisticated mount.
  • You wish to change your targets while viewing quickly.
  • You want to to do some terrestrial viewing with your telescope
  • You often travel; hence, you need a portable option.
  • You want a cost-effective option.

An EQ mount, on the other hand, offers more optical stability. It is easy to aim a telescope which is equatorially mounted for viewing celestial objects.

When the EQ mount is polar aligned, the axis is parallel to Earth’s axis. You only require a single motion to track stars in the sky.

An EQ mount becomes the perfect choice for experts. On the other hand, it is impractical to use an EQ mount for terrestrial viewing.

We have presented some more reasons. These indicate why an EQ mount is not the right choice for you:

  • You are enthusiastic about long exposure photography
  • You want guidance in catalogued coordinates for tracking celestial objects.

Recommended Reading:


  1. How Stuff Works
  2. Optics Central
  3. Celestron
  4. LCAS Astronomy
  5. Quora