The #1 most important item for astrophotography of deep-sky objects is your equatorial mount. The mount should always be the most expensive part of your setup. If you can afford nothing but a mount, just get an adapter and put your DSLR/lens on if you can, then upgrade to a scope later. The mount rules all.
Almost all best astrophotography mounts sold today, apart from a few premium offerings outside the scope of this article, are computerized German equatorial mounts. These astrophotography mounts are the most lightweight, versatile, and inexpensive option available to amateurs.
Sky-Watcher EQM-35 - Choice Under $850, Lowest Price
The EQM-35 is a relatively new entry by Sky-Watcher in the world of astrophotography mounts. It’s basically an Orion SkyView Pro/Celestron CG-4 mount with motors and GoTo installed.
The EQM-35’s lightweight and low cost make it great for beginning astrophotographers. And just like more expensive equatorial mounts, the EQM-35 is fully compatible with autoguiders, PC control software and anything else you need for imaging.
Sky-Watcher mysteriously claims a 22-pound weight capacity for the EQM-35, yet also doesn’t recommend shoving anything remotely near that heavy onto it. I put a Celestron C8 (about 14 pounds) on the EQM-35 and it was not the steadiest for visual astronomy, so I’d wager that in practice, the EQM-35’s weight capacity is closer to 15 pounds for visual use, and under 10 pounds for astrophotography. Thus, you are not going to be putting anything more than a telephoto lens or a small refractor on here for visual use.
If you’re not concerned about outgrowing its capacity, the Sky-Watcher EQM-35 is a good choice for a budget astrophotography mount.
Celestron Advanced VX - Choice Between $850-$1050
I’m probably going to get a lot of angry astrophotographers in the comments questioning how DARE I recommend the “horrid AVX” to beginners, but I’m doing it anyway.
Despite all the hatred it seems to receive, the Advanced VX is a workable – if not perfect – mount. It uses servo motors rather than steppers, and the declination axis has no bearings whatsoever – the result is that it has lots of backlash when slewing the mount around the sky and during autoguiding. However, there are plenty of fine images taken with Advanced VX mounts. If you can swing the extra $250 to buy the Sky-Watcher HEQ5 Pro I would definitely recommend doing so, but there is absolutely no shame in owning or using a VX.
The Advanced VX’s 2” diameter steel tripod legs are more stable in windy conditions than the 1.75” legs of similar mounts, and the Celestron NexStar+ hand controller is easier to navigate than the SynScan controllers of Orion and Sky-Watcher mounts (though this is irrelevant if you control the mount directly via a laptop).
I would not recommend loading anything over about 14 pounds for imaging on the Advanced VX. But for visual use, you can max out its 30-pound capacity with no issues – something to consider if you plan on using the mount with another telescope.
Sky-Watcher HEQ5 Pro - Choice Between $1050-$1350
This is the mount that I learned astrophotography on and a really solid choice. The Orion Sirius is functionally identical to the HEQ5 Pro – the only difference is that Sky-Watcher has better customer support and there seem to be more users of the HEQ5 Pro version than the Sirius out there.
The HEQ5 Pro has excellent tracking and guiding accuracy – it often guides at under an arc second – and is still quite lightweight and portable. The HEQ5’s 1.75” tripod legs are lighter than the Advanced VX so it does theoretically suffer some minor payload capacity loss, but this is made up for by its increased tracking accuracy and other features. The HEQ5 is compatible with EQMod drivers and a variety of hardware accessories to allow you to get the most out of it and have plenty of room to grow, and there are some who have made the belt and tuning modifications to further improve tracking and guiding accuracy with this mount.
I would recommend putting a scope no heavier than 15 pounds or longer than 1200mm in focal length on the SkyWatcher HEQ5. It struggles with my 6” f/9 Ritchey-Chretien, for instance, which is right around those limits.
Sky-Watcher EQ6R Pro - Choice Between $1350-$1600
The original EQ6 mount was more or less a scaled-up copy of the HEQ5. With the EQ6R Pro, however, Sky-Watcher has added a belt drive upgrade (previously only available as a warranty-voiding mod for skilled DIYers), improved polar alignment features, and ergonomic enhancements. The EQ6R’s payload capacity is no slouch, either. For visual astronomy you could load up to 44 pounds, while for astrophotography you should be able to fit between 20-25 pounds before vibration and other issues start to occur.
Downsides? Weight. The mount head alone is 38 pounds, with the tripod coming in at another 16.5 pounds. Maneuvering the mount head onto the tripod is difficult, to say the least, and then there’s the counterweights and your scope itself.
While the SkyWatcher EQ6R is certainly portable, it would be good to store it on a dolly or in a permanent enclosure/observatory if possible.
Orion Atlas Pro AZ/EQ-G - Choice Above $1600
The Sky-Watcher version of this mount doesn’t seem to be available in the US, unfortunately, so right now you can only get the Orion.
The Atlas Pro (also sold as the Sky-Watcher AZ-EQ6 outside the US), like the EQ6R, uses belt-driven stepper motors for superior accuracy.
The Orion Atlas Pro AZ/EQ-G also has a few pounds of extra capacity over the EQ6R and an alt-az mode that allows it to hold and track with 1 or 2 telescopes for visual astronomy, a nice bonus.