- 1) There are two types of telescope mounts – Altazimuth mounts and Equatorial mounts.
- 2) How to Setup an Equatorial Mount?
- 3) Our Favourite Equatorial Mount
A telescope mount is very important – it works as a motorized tripod. The main purpose of a telescope mount is to allow you to direct the optical tube at the object and take a good picture of it. You can track the motion of the object – whether it is the moon or a planet – by using a motorized telescope mount.
Motorized mounts are very important in astronomy as they allow for a very precise tracking of the planetary motion. It is important to choose the mount very carefully in order to capture the images of the celestial objects at their best.
1) There are two types of telescope mounts – Altazimuth mounts and Equatorial mounts.
In case of Altazimuth mounts, the telescope moves on the up-down and right-left axes, just like any photographic tripod.
In case of Equatorial mounts, the telescope moves along the polar axis and is pointed in the direction of the Pole Star.
Equatorial mounts are much harder to use as they require the polar alignment to be perfect. The tracking quality of an Equatorial mount will depend on how accurate the polar alignment is. Also, you need to make use of heavy counterweights to keep the telescopes of in place.
But the advantage is that equatorial mounts allow for a far more accurate tracking of celestial objects. They even improve the accuracy of the most ordinary telescopes.
2) How to Setup an Equatorial Mount?
It is actually quite easy to set up an equatorial mount. Sure, it’s not as easy as setting up an altazimuth mount – which is just like setting up a camera tripod. But once you set up an equatorial mount the first time, you will know how to do it again, for as many times as you like.
The advantage of an equatorial mount is that it only needs to be rotated around one axis so as to maintain the target object in your field of view.
Let’s understand how the Equatorial Mount works…
The planet Earth is tilted on its axis at 23.5°. When the Earth rotates around its axis, the stars in the sky appear to move across the sky through the night. To follow the movement of the stars, you have to move the telescope slowly in the opposite direction relative to the rotation of the Earth.
When you do this on the altaz mount, you will need to adjust two axes – the altitude and the azimuth. On the Equatorial mount, you only need to keep the polar axis parallel to the axis of rotation of the Earth, and there is no need to adjust it further. Also, you will need to rotate the other axis of the telescope called as the declination axis in order to focus on the target.
Follow the tips given here to easily set up an Equatorial Mount
You will need the following to get started.
A Compass – The compass should be easy to read under the red light.
Markers – For marking the position of the tripod leg once the mount has been aligned.
Red light torch – Essential for your vision; protects your eyes against the dim light.
Spirit level – Allows you to level the tripod easily.
You will also need a protractor, scissors and stiff cards.
Mark the position of the tripod
The tripod has to be placed in a single location. Once you decide where you place the tripod within your property, mark the positions of the legs on the floor.
Next, set up the tripod. Extend its legs to a suitable height, and make sure that the top of the tripod is as level as it can be. Tighten the bolts. Mark the height of each of the tripod’s legs, so that you will know where and how to position it the next time.
Setting up the equatorial mount
The very first thing to do when assembling the mount is to ensure that it is perfectly level. For this you will need to use a spirit level to check the level of the tripod head, and then attach the mount head on that. Once the mount has been completed, it has to be positioned roughly towards the north.
Okay, now let’s set the mount in the direction of true north. You can find the direction of the true north in your area on the Grid Magnetic Angle Calculator. You can then use the compass to adjust the mount in the direction of true north and away from the magnetic north.
In this case, make sure that the polar axis is properly aligned and set it for the latitude of your area or wherever you are mounting the telescope. You can check your position on the website iTouchmap.com. Once you know your latitude, mark a right-angled triangle on the stiff card which has one of the angles the same as your latitude.
This triangle can be used as a template to check the amount of adjustment needed to be made to the mount in order to get the perfect polar alignment. Hold the triangle against the mount, with the longest side of the triangle aligned against the polar axis, with the spirit level placed on the shortest side.
Right, you can now move the altitude adjustment bolt until the spirit level is perfectly level. The polar axis should be parallel to the Earth’s axis.
Focus on the Polaris.
The Polaris or the North Pole lies within an angle of 1° of the rotational axis of the Earth. Point the telescope towards it so that it is perfectly parallel to the polar axis of the EQ mount. Make sure that the Polaris is within the field of view of the finderscope and the lower power eyepiece.
Next, loosen the polar axis clutch to ensure the accuracy of the polar alignment. Once the Polaris is aligned accurately, it should move in a small circle within the field of view of the finderscope. In case it is not, make tiny adjustments to the azimuth and altitude of the mount head till it is so. You can now use the Equatorial Mount freely.
3) Our Favourite Equatorial Mount
There is a famous saying that “Your Telescope is only as good as your Mount” an we believe that. A good & stable mount can drastically improve your viewing experience. If you ask me, my favourite is CG-4 German Equatorial Mount and Tripod from Celestron.
- Accepts Vixen-style dovetail plates
- German equatorial mount and tripod
- Counterweights: one 7.0 lb/3.2 kg, one 4.0 lb/1.8 kg
- RA and DEC slow motion controls and setting circles
- Tripod: adjustable height, 1.75″ steel legs, center brace/accessory tray
So this is how to set up an Equatorial Mount. Feel free to ask any question you have on your mind in the comments below! 🙂