ClearSky ST17 Mini review: guiding in my seven-mount test
Where does it rank on our leaderboard
| Rank | Mount | Stars for Your Buck | Recorded UK price |
|---|---|---|---|
| 1 | TeSeek NanoTracker | 100 out of 100 | £52 |
| 2 | ClearSky ST25 | 94 out of 100 | £1,259 |
| 5 | JUWEI-14 | 89 out of 100 | £632 |
| 7 | JUWEI-17 | 85 out of 100 | £669 |
| 9 | ZWO AM5 | 58 out of 100 | £2,099 |
| 11 | ClearSky ST17 Mini | 56 out of 100 | £712 |
| 14 | Sky-Watcher Star Adventurer 2i | 42 out of 100 | £249 |
| 17 | Sky-Watcher GTi Mount | 33 out of 100 | £435 |
| 18 | Celestron CG5 | 24 out of 100 | £299 |
Contents
- 01 Where does it rank on our leaderboard
- 02 Specifications and features
- 03 In the hand
- 04 What would you put on it?
- 05 How well does it guide?
- 06 What is it for? Its features
- 07 Watch the review
- 08 Every row of my showdown, and the readings behind each one
- 09 Should you buy it?
- 10 Questions and more about this review
In 30 seconds
Stars for Your Buck 56/100
Reviewed 16 Oct 2025 Updated 24 Sep 2026
- Rank
- #11 of 18 mounts
- Verdict
- With reservations
Written by Damon Scotting 6 min read
Buy it if
- You want a very light head rated for 13 kg and can give it a sturdy tripod or pier.
- You image at short focal lengths, where regular periodic-error peaks matter least.
Skip it if
- You want the steadiest guiding for the money: the TeSeek 17 did better in the same test.
- You need a UK or US shop to buy from and a maker page to point to.
- You image at long focal lengths, where its periodic error shows.
“I think it's clear to identify its faults based on my readings, but even with that being said, an average total RMS of 1.09 for a £599 mount is nothing to be sniffed at.”
Specifications and features
Against the mounts I have reviewed
Compare with
| ClearSky ST17 Mini reviewed #11 of 18 | TeSeek 17 #6 of 18 | JUWEI-17 #7 of 18 | EM31 Pro #12 of 18 | JUWEI-14 #5 of 18 | |
|---|---|---|---|---|---|
| Recorded UK price | £712 | £536 | £669 | £1,679 | £632 |
| Stars for Your Buck | 56/100 | 88/100 | 85/100 | 52/100 | 89/100 |
| Average guiding RMS | 1.09 arcsec | 0.85 arcsec | 0.40 to 0.61 arcsec on M 31, 1.52 to 1.57 on M 45 | 0.73 arcsec | 0.98 arcsec |
| Best target in my showdown | 0.77 arcsec, North America | 0.45 arcsec, Heart | 0.40 arcsec, Andromeda (M 31) | 0.61 arcsec, Heart | 0.77 arcsec, Veil |
| Type | Harmonic drive equatorial mount; equatorial and theodolite modes | Harmonic drive (strain wave) equatorial mount | Harmonic drive (strain wave) equatorial mount | Harmonic drive (strain wave) equatorial mount | Harmonic drive (strain wave) equatorial mount |
| No-counterweight payload | 13 kg | 13.5 kg | 13 kg | 15 kg | 8 kg |
| Counterweight payload | 18 kg | 18 kg | 18 kg | 20 kg | 13 kg |
| Mount weight | 2.8 kg | 3.2 kg | 5.15 kg | 4.0 kg | 3.4 kg |
| Periodic error | not recorded | not recorded | Approximately 25 arcsec peak-to-peak in one owner's unguided, drift-corrected RA test; not a factory limit | not recorded | not recorded |
| Gearing | RA 17-100 harmonic, speed ratio 500, with brake; Dec 14-100, speed ratio 500 | Two size-17 harmonic gearboxes, 400:1 on both axes | Two size-17 harmonic reducers, 400:1 | RA and DEC: 17-type 100:1 strain-wave gear plus a synchronous belt, 300:1 overall; a brake on the RA motor | RA 400:1; Dec 100:1 |
| Control | not recorded | WiFi and Bluetooth app; ASIAIR | OnStep; WiFi, Bluetooth and USB; ST-4 and hand controller port | OnStep; ASIAIR in every session I recorded; my computer and StellaVita | USB-C, Bluetooth/Wi-Fi; controller/ST4 port |
| Power | not recorded | 12 V, 2 A | 12 V DC; no power output port | 12 V DC at 5 A in, 5.5 x 2.1 mm; 0.3 A tracking, 0.6 A slewing (the maker's sheet); the port panel on my unit: status light, Type-C USB, DC 12 V, a round hand-controller socket | 12 V DC, 3 A; 5.5 x 2.1 mm socket |
| Tripod or pier | not recorded | Metal latitude base included; no tripod | GEM4 base; 125 mm diameter; 12 mm centre column | 85 mm base, 3/8-16 fixing; optional EMTC44 tripod or EMH150 pier | 3/8 inch photo tripod; AM5 three-hole fixing |
| Polar alignment | Laser polar axis | not recorded | not recorded | not recorded | not recorded |
| Meridian flip | Automatic | not recorded | not recorded | not recorded | not recorded |
| Home and limits | Mechanical home position; patented mechanical limit | not recorded | not recorded | not recorded | not recorded |
| In the box | 1 x equatorial mount | The mount; no tripod | Head, data cable, counterweight bar, adjustment column, Allen key; no counterweight | Mount; hand controller; Vixen/Losmandy saddle; mounting adapter; 0.5 m and 2 m USB 2.0 cables; soft bag | Mount head |
In the hand
Clearsky
In a saddle
ST17mini
Top cap
Under the stars
What would you put on it?
The ST17 Mini's 13 kg and 18 kg ratings under a rig you can change part by part, then the same rig on six other mounts
How well does it guide?
My seven-mount showdown: the published average and per-target figures, and every ASIAIR reading I could read off the frames
“The ClearSky ST17 Mini would also be having a very good round if it wasn't for these peaks that keep boosting its total reading numbers.”
“The less said about the ClearSky ST17 Mini score, the better.”
“I could hear a little click sound going off at regular periods with the ST17 Mini.”
About this visualisation
This visualisation illustrates the guiding figures on this page: the published RMS for each target and the ASIAIR readings from my showdown. It is not the ST17 Mini’s precise recorded tracking, and the moving traces are drawn to those figures, not replayed from the mount.
What is it for? Its features
Two things it is for
Small head, big rating
A 2.8 kg head that carries 13 kg without a counterweight and 18 kg with one.
Laser polar axis
A laser polar axis for polar alignment, an automatic meridian flip, and a mechanical home position with a patented mechanical limit.
Watch the review
This £299 Telescope Mount Just Beat the £2,260 Mount… · published 16 October 2025 · 18:28 · Watch on YouTube · 67,163 views, 2,432 likes on 2 Oct 2026
Jump to
- 0:45 Mounts overview
- 6:34 What is a good RMS?
- 7:00 Big mounts: the Andromeda Galaxy
- 7:49 Round 1 results
- 8:56 Big mounts: the Heart Nebula
- 9:48 Deeper dive: polar alignment
- 10:57 Big mounts: the North America Nebula
- 12:46 Big mounts: the Veil Nebula
- 14:14 Final results
- 17:28 Conclusion
Transcript of the review video 3,807 words · 20 chapters · searchable
Press a time stamp to play from there.
0:00 Intro
0:04 Tonight's video may well be the greatest telescope mount review video on the planet. 0:06 And that is because I'm not going to be reviewing just one mount. 0:09 I'm going to be reviewing seven telescope mounts at the same time under the exact same conditions with precisely the same guiding equipment. 0:15 This video has taken months of preparation to do. 0:20 And I know it's going to be worth it because I'm going to be providing the astrophotography community with conclusive evidence on what each of these mounts are capable of doing from a relatively light polluted garden like this under the exact same conditions at the same time. 0:32 So let's find out what is the best pound-for-pound telescope mount on the market. 0:37 I'm Damon Scotting and this is Astronomical. 0:42 Right, so before we get started, let's take a look at the telescope mounts that I'm going to be reviewing in today's video.
0:45 Mounts overview
0:51 So, first up, we have the cheapest of the bunch, the TeSeek 11 mount. 0:52 I have just done a full review on this mount, so be sure to check that out in the description down below. 0:58 Our next mount is the ClearSky ST17 Mini. 1:00 It is also very small and supposedly capable of payloads up to 20 kg. 1:05 Oof. 1:05 Could this TeSeek 17 mount be the answer to all of our prayers? 1:10 It's a budget friendly mount that packs a punch and is available for under £500 before taxes and shipping. 1:16 Then we have one of my favourite mounts of the last few years, the JUWEI-14. 1:20 It's very wellmade, durable, and has traveled with me a lot over the last 6 months. 1:24 I'm also a very big fan of the Swiss Army knife of strain wave mounts, the EM31 Pro. 1:29 This is a strong rival to the AM5N, albeit with a lot more compatible accessories. 1:34 Speaking of which, here it is. 1:35 Arguably the most popular strain wave mount series in history. 1:39 It is also the only mount featured today that is available via UK and US retailers. 1:43 And finally, the telescope mount equivalent of a unicorn. 1:47 This colossal beast of a mount seems too good to be true. 1:49 It ticks all of my boxes and even features additional USB and DC power ports. 1:53 How cool is that? 1:57 So, we do have a huge variance in the mounts I'm going to be reviewing. 1:58 We have a £299 mount and we also have a 2,199 mount. 2:05 My biggest justification for making this video is that I love these third-party AliExpress mounts because they're so affordable. 2:11 Astrophotography is an amazing hobby. 2:13 I want more people to get into it. 2:15 But even to get started with the most basic equipment costs an absolute fortune, which is why I'm very keen on finding something that is the solution to all of our problems. 2:22 I don't want the go-to answer for what is the best beginner telescope mount to be a 2,199 AM5N telescope mount. 2:29 That's that's not okay. 2:32 That basically rules out 99.999% of the population from taking an interest in this hobby. 2:37 Instead, I want to be telling people, "Hey, check out this 299 telescope mount. 2:41 Yes, it only carries payloads up to 5 kg, but it still provides you very similar results to this 2K mount." 2:48 That's my hope. 2:48 I have reviewed all of these telescope mounts before individually, but now I want to do them at the same time so I have fair results and I could determine once and for all what is the best pound-for-pound telescope mount on the market. 3:01 So, the first part is going to be reviewing the smaller mounts and the second part is going to be reviewing the very heavy mounts, including the biggest telescope mount that I've ever tested. 3:09 Yeah, that one will be really special, right?
3:10 Small mounts: the Andromeda Galaxy
3:10 So, let's get stuck in with the small mounts and see how they fare. 3:13 So, right now, they're all looking at the Andromeda Galaxy and guiding at the exact same time. 3:17 And you can see the results displayed down here below. 3:19 I'm going to speed these up a little bit. 3:23 Every single one of them is guiding at 1 second long exposures. 3:24 And yeah, all in all, they're producing some very good results. 3:28 But perhaps most surprisingly out of these four telescope mounts, the one that seems to be fairing the best is the TeSeek 11. 3:34 Yeah, not too sure what to think about that. 3:38 So, the number we're going to be focusing on throughout this video is the total RMS value. 3:41 Much like in golf, the smallest score wins. 3:43 The higher this number is, the more our mount is having to correct his position to remain focused on our target. 3:48 This means our chances of having pinpoint stars are going to reduce, especially if this value exceeds something like 2.00, 00 which I've already noticed the JUWEI-14 and the AM5N mount do. 3:59 I am going to be testing these mounts out on four different targets but for our first test none of them are fared particularly well on the Andromeda Galaxy excluding the TeSeek 11 which is passed with flying colours somehow. 4:12 In fact, there was even a point during our observations where it was guiding at less than 0.4 RMS which is the last VI expected from such a lightweight and flimsy mount. 4:19 Now, when I was filming this video, the goal was to analyze the log graphs recorded throughout these observations later on. 4:27 But for some very frustrating reason, only the ASIAIR Plus recorded this data, while the ASIAIR Mini recorded absolutely nothing. 4:33 So, instead, I've had to write a script that will analyze each individual frame of my screen recordings to determine what the total RMS value was over the course of these observations. 4:42 It will then calculate the average at the end, give me a good idea as to how the mount's guiding was overall. 4:48 And in the case of a TeSeek 11, it really doesn't get much better than that. 4:53 Seriously, should we just call it there? 4:55 That is flawless. 4:58 This is just the first test of many that I'll be doing during the course of this video, and I figured now would be a really good time to let you know about my new channel, The Telescope Man, where I'll be posting a much longer version of this video where I dive into a lot more of the nittygritty details and explore the data in more depth. 5:16 something my fellow nerds will really enjoy. 5:18 I also talk a lot more about the control variables and how this was a fair test, but what could have been done to make it even fairer. 5:25 Make sure you subscribe to my new channel, The Telescope Man, if you love astrophotography content. 5:28 And to give you an idea of what to expect, here's a quick teaser.
5:31 The Telescope Man trailer
5:32 Hello, I'm the Telescope Man, and I'm on a mission to review every single telescope on our planet. 5:37 My goal is to show you what our night sky really looks like through each and every single one of them. 5:40 For many of us, when we point our telescopes towards the night sky, we expect to see this, but instead see this. 5:45 So, I'm here to set the record straight. 5:47 I'm going to be showing you raw footage of what our night sky really looks like from telescopes ranging from $50 all the way up to a billion dollars. 5:55 I'm also going to be taking on the most famous space telescope in history from my light polluted English garden. 6:01 Is it possible for me to outdo the Hubble Space Telescope? 6:05 Let's find out. 6:05 I'm going to be posting daily stargazing videos every day right here. 6:09 So, make sure you're following for the rest of the journey. 6:12 Thanks for watching and clear skies. 6:12 So, fortunately, I do have the guiding data for all of the AM5N guiding sessions, and as you can see from this graph here, it's a little shaky. 6:20 The total RMS over a very long period of 40 minutes was 1.53, which if we're being honest, isn't acceptable. 6:28 I do test the mount on the Andromeda Galaxy again in about 2 hours time, but the results are very similar. 6:33 To give you some form of a reference point as to what is a good RMS target, here is an example setup of the Askar SQA 55 and an ASI 533.
6:34 What is a good RMS?
6:39 This is a very wide field setup. 6:43 And as a result, an RMS of lower than 1.35 would be considered good. 6:48 But when you're using longer focal length setups with the same camera, your guiding needs to be much more precise, ideally under one. 6:53 So now let's see how the big mounts get on when pointed at the same target 2 hours later. 7:00 Now we have the ClearSky ST17 Mini, the EM31 Pro, the ClearSky ST25, and once again, the exact same ZWO AM5N mount.
7:00 Big mounts: the Andromeda Galaxy
7:10 This mount is acting as our control mount or our reference mount for both of the tests. 7:15 The first thing you can probably note is how absurdly long the AM5N was taking to calibrate its guiding. 7:21 Once again, the tracking numbers seem to be a bit better across the board. 7:24 Possibly because the Andromeda Galaxy was higher in the sky, and possibly because these heavy mounts have the same payloads as the smaller mounts, but are dealing with them a lot better. 7:33 With that being said, notice the regular peaks in the ST17 Mini's data. 7:38 This periodic error is heavily affecting its score, which is a terrible shame because otherwise it would be competing for the number one spot. 7:43 Okay, let's now find out where each telescope ranks in our first round of guiding results. 7:47 And would you look at that?
7:49 Round 1 results
7:50 I suspect this right here is why scientists for centuries have done repeat tests because the cheapest and least sturdy mount of the bunch has ranked first in the guiding results. 8:00 Shockingly, the AM5N finishes both last and second last with its two attempts. 8:05 But a well-deserved tip of the hat to the ClearSky ST25 and EM31 Pro as they take up the second and third spots for our first round. 8:11 Will this prove to be a one-off or can they keep this up? 8:15 Let's find out. 8:15 Right, let's move on to our next target, which is the Heart Nebula.
8:18 Small mounts: the Heart Nebula
8:19 Now, the Heart Nebula isn't that far away from the Andromeda galaxy in our night sky, but it does mean a fresh batch of guiding stars for our mounts to test themselves against. 8:28 And it looks like the TeSeek 11 is setting the record straight with its guiding scores as it seems to be averaging a total RMS of 1.5. 8:34 But now the TeSeek 17 is crushing it with some insanely low numbers. 8:40 The JUWEI-14 is doing a decent job and the AM5N has improved slightly on its previous round, but not by much. 8:46 The really interesting aspect of using the AM5N as our control mount throughout these tests is seeing how it fares at different points of the night. 8:54 The big mounts tests were conducted later on than the small mounts with the Andromeda Galaxy and Heart Nebula being higher in our night sky at this point and thus arguably easier to track.
8:56 Big mounts: the Heart Nebula
9:04 And I think you can definitely make that conclusion by comparing the results from the AM5N over these two rounds of guiding because as you can see the second time around these are good readings. 9:13 It's just about keeping up with the other big boys with EM31 Pro and ClearSky ST25 noticeably having strong rounds yet again. 9:20 Where does that leave us in terms of rankings?
9:21 Round 2 results
9:22 Well, when looking at the Heart Nebula, it's another win for the TeSeek mounts. 9:26 This time, the TeSeek 17 takes the golden medal as the TeSeek 11 swaps its gold medal for a red participation ribbon with a total RMS of 1.47. 9:34 Yeah, that first round of testing seemed a little too good to be true from the TeSeek 11. 9:39 I think we all generally expect the cost of the mount to correspond to its performance. 9:44 So, it feels like things are back to normal now that the cheapest mount is last in our table. 9:47 I did a bit of a deeper dive on the AM5N's guiding results, particularly its worst set out of these two looking at the Heart Nebula.
9:48 Deeper dive: polar alignment
9:55 And the odd part is that its results aren't down to a dodgy polar alignment. 9:59 In fact, it polar alignment is almost spot-on. 10:00 And ironically, out of all of the mounts, the AM5N and EM31 Pro were the only ones I accurately polar aligned. 10:07 This is because they're the only two mounts featured in today's video that don't have a laser pointer inbuilt, which allows me to very lazily, I might say, polar align the mount. 10:17 Seriously, the method I use for polar aligning the AM5N is far more precise than this, but it also takes a lot longer than just eyeballing the North Star, Polaris with your mount's inbuilt laser. 10:27 Moving on to our next target, the North American Nebula.
10:28 Small mounts: the North America Nebula
10:29 I'm expecting better results across the board. 10:33 This is because this stunning nebula is almost directly overhead at this point of year and filled with plenty of decently bright stars, making it great for guiding. 10:40 As you can see from these readings, all of the small mounts are performing very similar to one another. 10:45 Each sitting just below the 1.00 total RMS level with the TeSeek 11 being the only one that really strays above the 1.00 mark. 10:53 I think this round might belong to the AM5N which is performing much better.
10:57 Big mounts: the North America Nebula
10:58 As for the big boys, we are once again seeing some really good results. 11:01 all producing sub one readings for their total RMS with the AM5N performing almost the exact same as it did with the small mounts and the ClearSky ST25 having an absolute worldy. 11:09 And to be fair, the ClearSky ST17 Mini would also be having a very good round if it wasn't for these peaks that keep boosting its total reading numbers. 11:18 I think there's also something a little bit sus about the right ascension readings for the EM31 Pro here and how it seems to have some quite significant dips, but otherwise it's once again quietly having a good round. 11:30 So, our results for the penultimate round are excellent across the board with a TeSeek 11 the worst performer for the second round in a row.
11:31 Round 3 results
11:38 But hey, imagine being the worst performer with an average total RMS of 0.9. 11:45 I would take that as my mount in a heartbeat. 11:47 The heaviest mounts cleaned up this round with the AM5N making its first entry into our top three, taking home a silver medal and the ST25 and EM31 Pro making their way onto the podium yet again. 11:57 And our final target is going to be the Veil Nebula.
11:58 Small mounts: the Veil Nebula
12:00 So, let's see how they fare up against this supernova remnant. 12:03 Okay, let's go out of a bang for our final test by observing an explosive region in our night sky. 12:10 I'm showing the calibration stage once again because the AM5N is struggling once more. 12:13 Perhaps someone in the comments can highlight exactly what this might be. 12:16 I must emphasize that all of the mounts are using the exact same guiding scope, camera, guiding software, and imaging settings. 12:22 I discuss this point further in the extended edition of this video on my new channel, The Telescope Man. 12:28 Also, if you've enjoyed today's video and want to see more like it, then be sure to like this video, share it, and if you haven't already, subscribe. 12:35 So, in regards to the small mounts, it looks like it's going to be sub one guiding results across the board yet again with the TeSeek 11 having another good round and the AM5N finally starting to look like a 2,000lb telescope mount.
12:46 Big mounts: the Veil Nebula
12:48 Onto the big guys, and I think it's fair to jump to the conclusion that they have overall been better than the smaller mounts, producing much more consistent measurements than their smaller counterparts. 12:56 It does however really look like the ClearSky ST17 Mini is really struggling to cope even without accounting for its periodic error. 13:02 The rest of the bunch seem to be producing solid numbers with the AM5N mount eventually given readings that are almost identical to its scores in a small mounts test. 13:10 So, it is proving to be consistent. 13:12 We'll now take a look at the final round of results before then crowning our winner. 13:16 For the final round, it's the EM31 Pro that takes gold, the TeSeek 11 that sneaks into silver just ahead of the JUWEI-14 that claims its very first podium finish of the episode.
13:17 Round 4 results
13:27 The less said about the ClearSky ST17 Mini score, the better. 13:29 So, there we have it. 13:31 our tests have reached their conclusion, there are a lot, and I mean a lot of variables in tests like these. 13:37 The main reason it's important to conduct the measurements at the exact same time is because even the slightest bit of cloud can affect your readings. 13:45 It's very difficult to create a fair test, but I think I've done a fairly decent job in this video. 13:48 I am really keen, however, to hear what your suggestions would be going forward as to how to make them even fairer. 13:53 I'll try anything short of testing all seven mounts alongside each other at the same time. 13:59 Yeah, testing four mats at the same time was already messy enough. 14:01 I don't want to go through the stress of testing seven at the same time. 14:05 All right, it's time to find out our winner. 14:09 What is the best pound-for-pound telescope mount on the market?
14:14 Final results
14:21 In eighth place, we have the AM5N with its first set of test results. 14:21 grouped in with our small mounts. 14:23 A very underwhelming performance from this Titan. 14:27 Followed by the ClearSky ST17 Mini in seventh place. 14:29 I think it's clear to identify its faults based on my readings. 14:32 But even with that being said, an average total RMS of 1.09 for a £599 mount is nothing to be sniffed at. 14:39 Next up in sixth place is the AM5N again. 14:44 This time it is its second set of results alongside the big boys. 14:46 I mean, at least this mount has proven to be consistent. 14:50 My beloved JUWEI-14 mount squeezes in just under one RMS and does exactly what it says on the tin. 14:55 Nothing special, just gets the job done. 14:57 Its only real points deduction in the grand scheme of things is its lower payload capacity, which at 13 kg with a counterweight is still a very large amount. 15:06 Hang on a second. 15:06 Look at this guy. 15:09 The tiniest and lightest of the bunch only just misses out on a medal. 15:13 Could this mount change the astrophotography landscape going forward, making it more affordable to the masses? 15:18 Time will tell. 15:18 Taking home the bronze medal is another TeSeek mount. 15:23 The TeSeek 17 offers a lot of potential, particularly at £499 before taxes and shipping. 15:28 I tested the cheaper plastic shell version, and as you can see, it's done a really good job with only two mounts outperforming it. 15:36 The first of which is the jack of all trades. 15:38 The EM31 Pro mount has lived up to its price tag by delivering some excellent results. 15:42 Whilst reviewing this mount, I got the feeling that the company really tried their best to cater towards the astrophotography community and make a mount that works for you. 15:53 And at 0.73 RMS, I think you can safely say that they have delivered on that. 15:58 Finally, in first place, our golden medal winner is the absolute tank, the monstrosity, the ClearSky ST25 mount. 16:06 When I first saw the specifications of this mount saying that it can hold up to 30 kg as its payload, I knew this was a mount that I had to have. 16:16 But it's the design and additional accessories inbuilt that make it an absolute dream. 16:20 Before this video, it ticked all of my boxes. 16:22 But now, seeing how well it guides, I mean, it just defies belief. 16:26 A worthy winner of the title of best pound-for-pound telescope mount on the market. 16:31 And if you want help building your dream Astro rig, then why not try out my brand new Astro rig builder.
16:32 Build your own astro rig
16:37 It's the first of its kind and allows you to set your budget and pick the exact gear that suits you best. 16:40 All of the equipment included is stuff that I've already reviewed on my channel and will happily vouch for. 16:46 This is the first version of my website, so it will only get better from here on out. 16:49 There are buy now buttons which will take you straight to the items product page for further inspection. 16:54 And if you scroll further down, you will see a full list of the specifications for your selected gear. 16:59 It even calculates your field of view with your chosen setup as well as whether or not your payload exceeds the capabilities of the mount. 17:04 I've also included a gallery below filled with images I've captured using the telescopes and cameras featured to help give you a taste of what to expect. 17:12 As I'm sure you can imagine, this took a lot of time and effort for me to create from scratch. 17:17 So, please be sure to have fun with it. 17:19 Hit the randomizer button as many times as you can until you find your dream setup. 17:22 And share the web page with any fellow astrons who you think might also appreciate it. 17:27 Let me know what you thought of today's telescope mounts in the comments down below.
17:28 Conclusion
17:30 And if you own any of these yourself, then please share your own personal experience. 17:33 for the rest of us astrophotographers to read and discuss. 17:36 Yeah, the more hands-on reviews we get of these unknown telescope mounts that are very cheap, the better because then more of us can feel confident in purchasing them and getting into the hobby for a much cheaper cost. 17:47 I've been saying for a couple of years now that strain wave mounts are the best thing to happen to astrophotography in the last decade or so. 17:53 And that's because they make it so much easier without having to lug around counterweights and sorts. 17:57 They're incredibly small and lightweight. 17:59 And if we only have to pay £299 for them, even better. 18:04 Thanks for watching. 18:04 I'm Damon Scotting and this was Astronomical. 18:06 Don't forget to check out my new channel, The Telescope Man. 18:10 And if you want to purchase any of the mounts from today's video, then you can click on the links featured in the description down below. 18:14 Cheers.
Every row of my showdown, and the readings behind each one
| Mount | Stars for Your Buck | Andromeda | Heart | North America | Veil | Average |
|---|---|---|---|---|---|---|
| 1 ClearSky ST25 | 94/100 | 0.66″ | 0.69″ | 0.48″ | 0.80″ | 0.66″ |
| 2 EM31 Pro | 52/100 | 0.91″ | 0.61″ | 0.68″ | 0.73″ | 0.73″ |
| 3 TeSeek 17 | 88/100 | 1.19″ | 0.45″ | 0.83″ | 0.93″ | 0.85″ |
| 4 TeSeek 11 | 93/100 | 0.56″ | 1.47″ | 0.90″ | 0.76″ | 0.92″ |
| 5 JUWEI-14 | 89/100 | 1.37″ | 0.91″ | 0.88″ | 0.77″ | 0.98″ |
| 6 ZWO AM5N (second group) | 71/100 | 1.68″ | 0.85″ | 0.66″ | 0.78″ | 0.99″ |
| 7 ClearSky ST17 Mini | 56/100 | 1.17″ | 0.86″ | 0.77″ | 1.56″ | 1.09″ |
| 8 ZWO AM5N (first group) | 71/100 | 1.53″ | 1.28″ | 0.74″ | 0.86″ | 1.10″ |
ClearSky ST17 Mini
1.09″ average, 7th of 8
56/100 Stars for Your Buck
| Target | Readings | Mean | Range | RA | DEC |
|---|---|---|---|---|---|
| Andromeda | 14 | 1.04″ | 0.43″ to 2.06″ | 0.81″ | 0.49″ |
| Heart | 8 | 0.83″ | 0.60″ to 1.18″ | 0.58″ | 0.44″ |
| North America | 16 | 0.73″ | 0.55″ to 1.39″ | 0.50″ | 0.48″ |
| Veil | 11 | 1.58″ | 1.43″ to 1.75″ | 1.09″ | 0.93″ |
Should you buy it?
56/100 Stars for Your Buck
Pros
- Rated for 13 kg without a counterweight and 18 kg with one
- At 2.8 kg, the lightest head in my showdown rated for 13 kg or more
- Sub-0.9 arcsecond rounds on the Heart and North America nebulae (0.86 and 0.77)
- On its first night it rode in the saddle of my already polar-aligned EM31 Pro and worked like a treat
Cons
- “It does however really look like the ClearSky ST17 Mini is really struggling to cope even without accounting for its periodic error.”
- Regular periodic-error peaks in its guiding graphs; its worst round was the Veil Nebula at 1.56 arcseconds
- No periodic error figure, power rating or control details are published for it
- ClearSky has no product page for it, and no UK or US shop I checked lists it
This periodic error is heavily affecting its score, which is a terrible shame because otherwise it would be competing for the number one spot.
Who the ST17 Mini is for
Budget harmonic buyer
Skip
My recommendation is the TeSeek 17: it guided better in the same showdown (0.85 against 1.09) and carries 13.5 kg.
Travelling imager
Buy
At 2.8 kg for a 13 kg rating it is the lightest head of its class that I tested, as long as a solid tripod travels with it.
Long focal length imager
Skip
Its regular periodic-error peaks would show in long exposures; the EM31 Pro or the ClearSky ST25 guided far more steadily.
Owner of a light photo tripod
Skip
On a light tripod and head its guiding suffered in my test; it needs a sturdy tripod or a pier.
Buyer who wants a dealer and support
Skip
No UK or US shop sells it and ClearSky publishes no page for the Mini; if it fails you are dealing with TeSeek's store or an AliExpress seller.
Owner of a solid pier or wedge
Buy
Seated on something rigid it behaved well for me, and its 13 kg rating leaves room for a mid-sized refractor.
Three alternatives I have reviewed
- TeSeek 17 13.5 kg without a counterweight, 0.85 in my showdown 88/100 £536 Read the review
- ClearSky ST25 The showdown winner at 0.66, 20 kg without a counterweight 94/100 £1,259 Read the review
- JUWEI-17 13 kg without a counterweight, my default carrying mount 85/100 £669 Read the review
Questions and more about this review
Reviewed by
Damon Scotting
The Telescope Man Verified
BSc (Hons) Physics with Astrophysics and Cosmology, Loughborough University PGCE / QTS, University of Nottingham
About Damon About Damon Damon Scotting is The Telescope Man. He holds a BSc (Hons) in Physics with Astrophysics and Cosmology from Loughborough University and a PGCE with QTS from the University of Nottingham, and taught physics in secondary schools before becoming an astronomy creator. He is a contributing writer for BBC Sky at Night Magazine and the author of 42 Wonders of Our Night Sky, and his photograph of the galaxy M100 with the dwarf planet Ceres was Highly Commended in the Astronomy Photographer of the Year 2024 competition run by Royal Observatory Greenwich. He has appeared on the BBC's Blue Peter. More than 750,000 people follow his astronomy channels on YouTube, Instagram and TikTok, and he has reviewed more than 140 telescopes, mounts, cameras, filters and accessories hands-on for this site. More about Damon · How I test · Damon's book
I review all kinds of gear: most of it I buy, some is gifted and some is loaned, and all of it is reviewed the same way. How this site is funded
Seven questions, answered
Questions about the ClearSky ST17 Mini
Reviewed 16 October 2025 ·Updated 24 September 2026
I review all kinds of gear. Most of it I buy, some is gifted and some is loaned, and all of it is reviewed the same way: no company sees or approves a review before it is published. How this site is funded
- How well does the ClearSky ST17 Mini guide? In my seven-mount showdown it averaged 1.09 arcseconds total RMS, seventh of eight rows: 1.17 on the Andromeda Galaxy, 0.86 on the Heart Nebula, 0.77 on the North America Nebula and 1.56 on the Veil Nebula. How well does it guide? ↓
- How much can the ST17 Mini carry? It is rated for 13 kg without a counterweight and 18 kg with one, from a 2.8 kg head. The specifications and the comparison table ↓
- Why did its guiding graph show regular peaks? The peaks came at regular intervals, which points to periodic error. I also heard a regular click from it, and the light tripod and head I stood it on in the showdown were not built for that load. How well does it guide? ↓
- Is the ST17 Mini the same as the ClearSky ST17? No. The full-size ST17 is a separate, heavier mount (4.7 kg against 2.8 kg); the AliExpress listing I linked for the Mini has since been withdrawn. The specifications and the comparison table ↓
- Where can I buy the ClearSky ST17 Mini? No UK or US shop I checked lists it, and ClearSky has no product page for it. The verdict, the readers and the sellers ↓
- Does the ST17 Mini have a polar alignment laser? Yes. Every mount in my showdown except the ZWO AM5N and the EM31 Pro has a laser pointer built in. Watch the review ↓
- What should I buy instead? The TeSeek 17 guided better in the same test (0.85) and carries 13.5 kg; the ClearSky ST25 won outright at 0.66 if you need a bigger mount. The verdict, the readers and the sellers ↓