Your image will gradually rotate, though, leading to distracting star trails in the background and decreasing the amount of detail in your photograph. If the extra cost is a concern, the best policy is probably to get the best equatorial telescope you can afford and add stuff like a tracking drive, special filters and a dedicated camera attachment as you can afford them. Many amateur astronomers love tinkering with their own equipment almost as much as using it.
This is not, however, an easy project. For now, he lives in a Latin American surfing town and maintains a science blog. Skip to primary navigation Skip to main content Equatorial Telescope Mounts. Thank you again. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. Skip to content. Blog Our Store Search for:. Remember this wonky drawing from the previous blog? There are two ways of setting this angle on your equatorial mount.
Altitude scale and adjustment bolts A more accurate, if fiddly, way of doing it is to again use your phone. The equatorial mount all set up Short cuts for aligning your equatorial mount next time Here are some ways to save time setting up your equatorial mount.
Always set up in the same spot eagle-eyed readers may have noticed I have some small pavers set into my lawn. Take note of some landmark you can use for orientation. I know that the fence post in the background is roughly due south of my telescope.
You can see this in the photo above where you can see my hand holding the compass. Learn how to find Sigma Octantis with a pair of binoculars. This is for the more advanced astronomers, especially astrophotographers. Further reading The Astronomical Society of South Australia has a nice easy web page that provides some more detail on polar alignment, including how to use Sigma Octantis.
Pleasant in tone. Leave a Reply Cancel reply Your email address will not be published. The primary structure of a GEM is a T-shape, with the right ascension axis at the lower diagonal position, and the declination axis on top. The telescope is placed on the DEC axis, with a counterweight attached at a balanced position on the other end. A GEM is the best possible choice for long-exposure astrophotography.
In recent years, a new take on the German equatorial mount design has surfaced. The image below shows a new center-balanced design from iOptron, the CEM When the telescope is able to secure a target in place for hours at a time, you can then attach your camera and collect several long exposure images.
This is essentially what deep sky astrophotography is all about, and almost every other aspect is geared towards improving this tracking accuracy with techniques such as autoguiding. Equatorial telescope mounts come in many shapes and sizes, each having their own qualities in terms of maximum payload capacity and tracking performance.
The equatorial EQ mount head is fastened to a tripod that elevates the telescope to a practical height for observations or photography. The tripod should be sturdy and level to provide a stable foundation. In general, it is best to keep the tripod as low to the ground as possible to maximize stability.
Equatorial telescope mount tripods and piers come in several sizes and materials. Amateur astrophotographers go to great lengths to ensure that their equatorial telescope mount head is well supported and secure. My first computerized mount for astrophotography was a Celestron CG The polar alignment process involves identifying the latitude and longitude coordinates of your location, so that the angle of the polar alignment scope is pointed towards the north NCP or south SCP celestial pole.
The declination axis is the side-to-side movement of the EQ mount, that provides the ability to point the telescope in any direction of the night sky. An equatorial telescope mount seamlessly balances the movement of the two axis simultaneously. An iOptron CEM60 with a large refractor telescope mounted on top.
Many equatorial mounts include a polar finder scope with an illuminated reticle, that provide you with a useful guide to align the polar axis. Polar alignment is absolutely critical for accurate tracking and pointing accuracy. If the RA axis of the equatorial mount is not aligned with the celestial pole, its internal clock drive is not in sync with the rotation of the Earth.
There are a number of tools you can use to help polar align your equatorial mount, such as:. Speaking of balance, the actual balancing of the weight on top of the mount the payload is extremely important.
An equatorial telescope mount requires an even balance in both axis to perform optimally. A payload that is too heavy on one side of either axis can result in poor tracking performance, and squander the effectiveness of autoguiding. In terms of astrophotography, the telescope and additional accessories such as camera gear must be balanced and organized. Loose cables that could snag while slewing to a target or over time while tracking can ruin a long exposure image or damage the mount.
The same care must be given to the profile of the equipment mounted, as you want to avoid the telescope or camera from ever striking the legs of the tripod. This in turn leads to high levels of tracking performance at an affordable price point, but at the tradeoff of being heavier and less portable.
For most amateur astronomers, a quality German Equatorial Mount is the right choice to capture the very long exposures required for deep sky astrophotography. Although these mounts can be used for visual astronomy too, they can present awkward viewing angles when looking through an eyepiece. For visual use, an alt-azimuth mount is a better choice. All in all, though, the German Equatorial Mount is the best choice for imaging with anything other than a small telescope or camera lens. Shop German Equatorial Mounts.
Best for beginning astrophotographers and those who want ultimate portability. These mounts are best for imaging widefield targets like the Milky Way Galaxy and some larger deep sky objects like the Orion Nebula when paired with a longer focal length lens or telescope.
Unlike their close German Equatorial Mount cousins, star trackers are designed to carry a light payload, are much more portable, and aren't as expensive.
Another key difference from German Equatorial Mounts is that most star trackers don't have go-to capability, meaning you'll have to point them manually. Some heavier-duty star trackers, like the Star Adventurer Pro or SkyGuider Pro, can carry enough weight to hold a telephoto lens or even a small and ultralight refractor telescope such as the Radian Raptor Although these star trackers can't track as accurately as larger German Equatorial Mounts and often only track in one axis RA instead of two, they are usually still a great choice for anyone just starting out in astrophotography.
Explore Star Trackers. This makes them great tools for both visual observing and imaging, which is ideal for those who enjoy swapping back and forth between the two such as for public outreach events. Unlike converting an alt-az mount to an equatorial mount by using a wedge, these hybrid mounts have a true counterweight system like German Equatorial Mounts do, and can therefore be used with excellent results for astrophotography. When used in alt-az mode, some hybrid mounts can even carry two telescopes of similar weight at once.
This can give an added benefit of observing at multiple focal lengths without swapping eyepieces. Of course, the added functionality of both AZ and EQ modes mean that hybrid mounts cost more than alt-az or equatorial mounts on their own, but hybrid mounts are a fitting choice for those who frequently do both.
Explore Hybrid Mounts. Altitude-azimuth mounts have the ability to become equatorial mounts with the addition of a component called an equatorial wedge. The wedge sits between the mount and the tripod and allows the user to tilt the mount to an angle matching their location's latitude.
By doing this, the wedge allows an alt-az mount to be used equatorially and therefore can track the night sky without any field rotation for astrophotography. Equatorial wedges are a great choice for planetary imagers who may already own an alt-az mount, and they can also do short-exposure deep sky imaging too. However, for long exposure deep sky imaging, equatorial wedges fall short.
This is because unlike German Equatorial Mounts, equatorial wedges don't utilize a counterweight system. This puts added torque on the motors inside the mount as they have to support the entire weight of the telescope. In turn, tracking performance over long exposures can suffer if a heavy-duty mount isn't used, and so equatorial wedges are less ideal for most long exposure deep sky imaging compared to German Equatorial Mounts that use a counterweight system.
Overall, equatorial wedges can be an excellent choice for those looking to upgrade their existing alt-az mount to track equatorially on a limited budget. Explore Equatorial Wedges.
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