Celestron Advanced VX (AVX) mount review

The Celestron AVX mount is an excellent and affordable choice for beginner astrophotographers. With its reliable connectivity, autoguiding, and PEC option, it allows for capturing stunning, sharp images of deep sky objects. The mount’s portability, user-friendly knobs, and easy setup make it convenient to use. Whether connecting to the handcontroller or a PC, it offers versatility. However, keep in mind its limited payload capacity of about 5 kg (12 lbs) for astrophotography, and 13kg (30 lbs) for visual use. While some backlash may occur over time, it can be resolved easily. For an affordable and reliable astrophotography mount, the AVX comes highly recommended based on five years of personal experience.

I’m excited to share this review with you and discuss the mount I’ve been using for over five years, the Celestron advanced VX equatorial mount, or AVX in short. I have been using this mount for visual observations as well as planetary and deepsky astrophotography, using different telescopes and cameras. Below, I will explain each of the points I have mentioned in more detail, and I’ll compare the AVX to some competing mounts that are available. I also share some video tutorials on how to setup and polar align the mount and how to connect the mount to your laptop or PC.

Introduction

After its original introduction in 2014, it remains one of the cheaper entry-level mounts that you may consider when starting your astrophotography hobby. It is one of the few mounts below the $1000/ €1000 range, so it is definitely worth your consideration when starting your astrophotography hobby. In this review, I’ll write about the pros and cons that I’ve experienced over the past years, and I will provide tips and video tutorials on how to setup and align this mount for astrophotography. I will not mention all the specifications of this mount in this blog, but you can check out this video where I go through all the specifications of this mount.

Main advantages of the Celestron AVX

Price

An obvious advantage is the price of the AVX. At this moment it sells for $1179 (May, 2023) and is regularly “on-sale”, making it one of the few entry-level astrophotography mounts around the $1000 dollar range you can use with a decent telescope and camera. For the latest prices check Agena (USA/WW), or Astroshop (EU/WW).

Weight

The tripod of the AVX weighs 18 lbs (8.16 kg) and the mount head weighs 17 lbs (7.71 kg). This makes this equatorial mount one of the lighter mounts you can use when getting into astrophotography using a telescope. For people like me who do not (yet) have the luxury of an observatory in the backyard, this is a big plus. The relative portability of the mount also makes the AVX suitable for astrophotography in remote locations. As I’m setting up and tearing down my AVX with every new imaging session, I’m very happy that I can carry it around without breaking my back.

Easy to setup

Even when this is your first equatorial mount, you will be able to figure out how to setup this mount. Some of the specific advantages are that the AVX has large alt-az and dovetail knobs which make it easy to polar align the mount and to secure your telescope and camera on its saddle plate. Of course, if your completely new to the game, you will first have to learn how to perform these procedures. I have made two tutorial videos on how to setup and polar align your mount. The first video is suited for those who have never set up the AVX mount. The second video shows how to polar align your telescope “like a pro” :-).

Over the years I’ve become accustomed to the mount, and it takes me about 15 to 20 minutes complete my setup and polar alignment with the AVX. In the video below, I mention five tips to get a good polar align with the Celestron Advanced VX mount.

Nexstar + Hand Control

The NexStar+ Hand Control for its equatorial mounts (Advanced VX, CGEM, CGEM II, CGX, and CGX-L series) is upgradeable via the internet. The latest update will enable you to automatically slew your mount to 40,000 object that are in its database. Importantly, you can connect the AVX to your PC via the hand controller which enables you to remote control your mount via the Celestron ASCOM driver. The newer AVX versions have a mini-USB connection (cable not included), so you would need a usb-to-usb cable to connect your hand controller to a USB input on your PC or laptop. With the older AVX versions, this procedure used to be more cumbersome. The older hand controllers are outfitted with an RJ11 (telephone) output, which needs to be converted to an RS232 output. In turn, the RS232 output needs to be connected to a a RS232 to USB converter, which then connects to a USB cable you can plugin to your PC or laptop. So the newer USB mini output on the hand controller is definitely a step up, although the most attractive solution would be to connect a USB cable directly to your mount, or to have a remote wireless connection to your mount. This is not possible with the Celestron AVX mount. If you want to learn how to perform a star alignment procedure with either your hand controller or do remotely by using NexRemote on your PC or laptop, then this video may be useful.

Guiding port and Periodic Error Correction

Any aspiring astrophotography mount should include a guiding port and the AVX has one too. In a nutshell, guiding refers to the option to connect a guide camera to your mount. In combination with guiding software such as PHD2, your guide camera is able to send minor corrections to your mount while tracking a star that is in the vicinity of the Deep Sky Object you want to image. I will not get into guiding in this blog but believe me, it is a must when you want to take multi-minute pictures of many deep sky objects. The mount also includes Periodic Error Correction to further perfect your guiding. PEC basically records potential inaccuracies that are in the servo motors, wheels and worms of your mount that drive your Right Ascension and Declination axis. PEC can be switched on via the hand controller, or via PECtool – a software program which you can install and run on your computer. PEC tool makes a 10 minute recording of any potential inaccuracies when tracking deep sky objects with guiding initiated. After those 10 minutes, you can playback the recording which should help improve the tracking accuracy of your mount even further. PEC works in combination with guiding software.

Disadvantages and limitations of the Celestron Advanced VX mount

Payload capacity

This is not really a disadvantage, but rather a limitation when you are searching for mounts below the $1000 dollar range. The maximum payload capacity is 30 lbs (13.6 kg), which is actually quite generous. However, the servo motors – although decent – are not of the highest quality, so it would be wise if you divide that number by 3 on this mount to get the maximum payload when using the AVX for deepsky astrophotography. Taking multi-minute pictures of DSO’s (Deep Sky Objects) requires a great amount of tracking accuracy. When putting the maximum payload (e.g., a heavy telescope, camera, guidescope, guidecam) on the AVX, tracking will become less accurate. In my experience, the AVX still tracks accurate enough to image solar system objects such as the moon and our planets with a heavy payload, but it becomes increasingly challenging to image DSO’s in combination with a heavy payload for two obvious reasons. The heavy payload puts more strain on the RA and DEC servo motors, making in it harder to accurately track DSO’s. Moreover, bigger scopes usually have a narrower field of view which makes tracking all the more challenging.

Backlash issues

Before getting into this issue I have to say that – for the price range this mount is in – it has decent servo motors that provide accurate enough guiding for astrophotography, especially in combination with wide(r) field refractors. This being said, the guiding inaccuracy has increased over the five years of using this mount due to backlash. In short, backlash cause delay in the movement of the RA and DEC axes. You can notice this when using the direction arrows on the hand controller, or when autoguiding software attempts to send corrections to your mount which tell the AVX to change the direction of the RA or DEC position. For instance, when the mount has to change its direction from guiding north to guiding south, backlash issues will cause the mount to respond only after several seconds have past, after which the mount starts to move into the other direction. I’ve tried to deal with this backlash issue by repositioning the gears of the RA and DEC motors and this improved the response time of my mount when receiving instructions from my PHD2 guiding software. However, readjusting the mount yourself will probably void your warranty, so I would not recommend doing so when you still have warranty. If you are interested in how to deal with backlash and you are not bothered by voiding your warranty, this video might be useful to you.

Connection to PC/Laptop runs through hand-controller

A small nuisance is that you cannot run a USB cable directly from your mount to your PC or Laptop to control the mount using the Celestron ASCOM driver. Or even better, it would be great to connect wirelessly to your mount. Instead, a USB cable has to be connected to your hand controller. As mentioned, the newer models have a USB mini output on the hand controller, which makes it easier to run a USB mini to USB cable to connect your hand controller to your PC or laptop, enabling you to control the AVX using free software such as NexRemote or stellarium. The older models have an RJ11 output (telephone type of output). It requires a RJ11 to RS232 cable, and an extra R232 to USB converter to connect the older models of the Celestron Advanced VX to a USB port of your PC or Laptop.

What is the guiding accuracy of this mount?

Actually, I’m somewhat reluctant to state my guiding accuracy as it depends on a lot of conditions. The accuracy of your polar alignment is one of them, the kind of weather (winds, atmospheric conditions) is another, and then we should also take into account the weight and balance of your payload (i.e. scope, imaging camera, guidescope, guidecam, and so on). Finally, the accuracy may also depend on how you have setup your guiding software (e.g. PHD2 setup), the quality of your guidecam and guidescope, and whether you use Periodic Error Correction. All this being said, I have to say that – on average over the past five years – my guiding accuracy with the AVX mount has been around 1 arc second, sometimes a bit worse, oftentimes a bit better. This is with a payload capacity of about 5 kg (12 pounds). I’m using a TS Photoline 80MM F/6 APO refractor, a ZWO ASI 1600MM pro imaging camera and an ZWO electronic filter wheel with an orion 50MM guide scope and a ZWO ASI 120MC guidecam. For a complete overview of my astrogear I’ve accumulated over the years, check this website.

The competition

Obviously, the Celestron AVX is not the only astrophotography mount on the market in this price range. I wrote this separate blog about good-quality beginner telescope mounts that are available for astrophotography. I suggest you read this blog which I regularly update with new telescope mounts that become available on the astromarket.

Celestron Advanced VX – Conclusion

Over the past five years the Celestron Advanced VX mount has become my trustworthy companion for astrophotography. It never failed to connect, I was always able to get a good polar alignment and – using PHD2 and PEC tool – I was able to capture multiminute (usually 5 minute) images of the various DSO’s using ther my 80mm or 102mm refractors. If you are interested in my images, you can visit my photogallery. The backlash has become worse over the past years, meaning that the mount needs more time to react to the guiding corrections it gets from PHD2, but the guiding is still accurate enough to perform astrophotography. Setting up the mount is relatively easy, the knobs and clutches are sturdy and I always felt that my astro gear (telescopes, cameras) was securely fixed on the Saddle plate of my AVX. Of course, I advise you to do your own research and compare the AVX to its competitors, like the telescope mounts described in this blog. I would also encourage you to check out astronomy fora and pictures taken with the AVX mount to get a better sense of what the capabilities of this mounts are. But all in all, after five years of use, I can highly recommend it as an affordable mount to start your astrophotography adventure.

The Celestron Advanced VX Telescope Mount is currently available at Agena (USA/WW), and Astroshop (EU/WW).

Clear skies!