How to set up an equatorial mount

The viewfinder and mount head are placed on a tripod. The RA axis should point towards the north celestial pole. For motorized equatorial mounts, some short unguided photography is possible, provided your alignment is sufficiently accurate and your motor is set to track at sidereal speed (the speed at which stars appear to move in the sky due to the Earth’s rotation). Place the MOUNTING HEAD on top of the tripod.

This orients the polar axis of your equatorial mount so that it is parallel to the Earth’s rotation axis, making it easier to track celestial objects as they rise and set. It may be easier to set up a camera-type altazimuth (altaz) mount, but an equatorial mount has the advantage that you only need to rotate about one axis to keep your target object in the field of view, rather than two. It may be easier to set up a camera-type altazimuth (altaz) mount, but an equatorial mount has the advantage that you only need to rotate about one axis to keep your target object in the field of view, rather than two. With the equatorial mount, once set up for the southern hemisphere, only one axis needs to be adjusted.

The equatorial mount is designed, (once polar aligned, set up and attached to a target) to follow your target across the sky. Screw the counterweight bar into the head of the mount. Attach a SLOW MOTION CABLE to the small D-shaped axes of the AR and Dec. The first time I used my equatorial mount, I never thought to align the finder and it was frustrating.

This beginner’s guide to mounting and using an equatorial mount is quite long, so it is divided into sections. When you mount your mount, make sure it is as level as possible – use a small bubble level on the tripod head before attaching the mount head. The first thing you should do is take your finder and align it. Newcomers to astronomy often shy away from equatorial mounts because they are told they are complex to set up and use.

The polar axis of an equatorial mount is parallel to the Earth’s axis of rotation and therefore does not need to be adjusted. In this part I will show you the steps to set up your equatorial mount well enough to get decent tracking for visual work.

equatorial mount

Learn more about equatorial mounts and tripodsEquatorial mounts for telescopes are designed to make it easier to track celestial objects as they move across the night sky. Accurately track the night sky for long exposure astrophotography and planetary imaging with OPT’s selection of equatorial mounts. The polar axis of an equatorial telescope mount should point toward the north celestial pole, which is the point in the sky where all the stars appear to rotate. Although this type of motion is less intuitive and a bit more awkward for traditional observing, it is essential for astrophotography because of its ability to track an object without field rotation.

As the Earth rotates throughout the night, the stars appear to move in an east-west motion, just as the sun rises and sets each day. Astronomy buffs and astrophotographers rely on an equatorial telescope mount to follow the apparent motion of the night sky. I predict that many aspiring amateur astrophotographers will quickly outgrow a non-powered equatorial mount. This can be accomplished using a polar alignment telescope, software-assisted methods built into the on-board computer systems of some German equatorial mounts, or a combination of these techniques.

The RA motor of an equatorial mount moves slowly in a single motion so that the speed of movement is adequate for long-exposure astroimaging. In turn, tracking performance at long exposures can suffer if a heavy duty mount is not used, making equatorial wedges less ideal for most long exposure deep sky imaging compared to German equatorial mounts that use a counterbalance system. Because of this movement, a telescope mount must move at the opposite speed that the Earth rotates to keep objects in the sky centered in the view through a telescope. However, if you plan to dive into astrophotography, you will need a sturdy equatorial mount with a minimum of one motor on both axes, manual control, and a weight capacity well beyond the weight of your optical components and OTA accessories.

Equatorial mounts have the ability to track celestial objects throughout the night with a high degree of accuracy and are primarily used for astrophotography. All telescope mounts have this capability, but equatorial mounts, in particular, take into account the user’s location through latitude by adjusting the tilt angle of the mount. But if your goal is to take deep sky astrophotography images with your camera, you’ll want to invest in a sturdy equatorial telescope mount. German equatorial, or GEM, mounts are the ideal choice for deep sky astrophotography, as well as planetary astrophotography with a telescope.

This design allows the attached instrument (your camera or telescope) to remain fixed on a celestial object by driving an axis at a constant speed. IOptron GEM28 GoTo Equatorial Mount & Tripod – Fairly new on the scene, the iOptron GEM28 has a load capacity of 28 pounds, but weighs only 10 pounds without the counterweight. Alternatively, if your budget allows, buy an equatorial mount with astrophotography capability now, knowing it will be golden if you decide to try your hand at imaging later. For most amateur astronomers, a quality German equatorial mount is the right choice for capturing the very long exposures needed for deep sky astrophotography.

With so many varieties of equatorial mounts available, it can be difficult to determine which one is best for your astrophotography equipment. An equatorial mount is an instrument mount that compensates for the Earth’s rotation by having an axis of rotation parallel to the Earth’s axis of rotation. This allows the mount to not only keep a celestial object centered in the view, but to prevent it from appearing to rotate, as these objects follow their natural arc motion across the sky for many hours.

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