ClearSky ST25 review: the harmonic mount that won my showdown
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 |
| 3 | TeSeek 11 | 93 out of 100 | £252 |
| 5 | JUWEI-14 | 89 out of 100 | £632 |
| 8 | ZWO AM5N | 71 out of 100 | £2,099 |
| 13 | ZWO AM3N | 46 out of 100 | £1,599 |
| 15 | Celestron CGX | 38 out of 100 | £2,469 |
| 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 From the review video
- 05 What would you put on it?
- 06 How well does it guide?
- 07 What is it for? In my words
- 08 Watch the review
- 09 Every row of my showdown, and the readings behind each one
- 10 Should you buy it?
- 11 Questions and more about this review
In 30 seconds
Stars for Your Buck 94/100
Reviewed 16 Oct 2025 Updated 24 Sep 2026
- Rank
- #2 of 18 mounts
- Verdict
- Damon's pick
Written by Damon Scotting 7 min read
Buy it if
- You image with a heavy rig and want a harmonic mount rated 20 kg without a counterweight on my card and 30 kg with one.
- You want power and USB outlets on the mount so fewer cables trail down to the pier.
- Guiding matters most: it had the best average of the eight rows in my showdown.
Skip it if
- You need a travel mount: the head alone weighs 8.5 kg.
- You want a UK or US retailer and local support: it ships from China through TeSeek's store and AliExpress.
- Your rig is small: a lighter harmonic mount such as the TeSeek 11 or the JUWEI-14 costs far less.
“If ZWO or Sky-Watcher had released something this powerful at this price, it would have dominated the market for years.”
Specifications and features
Against the mounts I have reviewed
Compare with
| ClearSky ST25 reviewed #2 of 18 | EM31 Pro #12 of 18 | ZWO AM5N #8 of 18 | ZWO AM7 #10 of 18 | MLAstro SAL-33 #4 of 18 | |
|---|---|---|---|---|---|
| Recorded UK price | £1,259 | £1,679 | £2,099 | £2,599 | £937 |
| Stars for Your Buck | 94/100 | 52/100 | 71/100 | 58/100 | 91/100 |
| Average guiding RMS | 0.66 arcsec | 0.73 arcsec | 0.99 and 1.10 arcsec | 0.85 arcsec | 0.7 to 0.8 arcsec |
| Best target in my showdown | 0.48 arcsec, North America | 0.61 arcsec, Heart | 0.66 arcsec, North America | 0.58 arcsec, M 51 (18 min average) | 0.41 arcsec, Elephant's Trunk |
| Type | Harmonic drive go-to equatorial mount, both axes | Harmonic drive go-to equatorial mount | Harmonic drive go-to equatorial mount | Harmonic drive go-to equatorial mount | Harmonic drive go-to equatorial mount |
| No-counterweight payload | 20 kg on my spec card; ClearSky rate it 30 kg | 13 kg on my spec card; EMCAN rate it 15 kg | 13 kg on my spec card; ZWO rate it 15 kg | 20 kg | 15 kg |
| Counterweight payload | 30 kg on my spec card; TeSeek list 30 to 35 kg | 20 kg | 20 kg | 30 kg | 20 kg |
| Mount weight | 8.5 kg head (9 kg in all) | 4.0 kg | 5.5 kg | 6.75 kg head | 5.3 kg |
| Periodic error | not recorded | not recorded | ±10 arcsec | ±10 arcsec | not recorded |
| Gearing | Harmonic reducers with timing belts, 300:1 on both axes (25-type RA, 20-type Dec) | Strain-wave gears with belts, 300:1 both axes | Harmonic drive | Harmonic drive | Harmonic drive |
| Control | OnStep over USB, Bluetooth, WiFi or ST-4; works with the ASIAIR | OnStep: hand controller, ASIAIR, ASCOM, INDI | ASIAIR | ZWO app over Wi-Fi and Bluetooth, USB, ASIAIR; handset in the box | OnStep X |
| Power | 12 to 15 V, 2 to 5 A in; four 12 V 3 A DC outlets and four USB ports on the saddle | 12 V DC, 5 A | 12 V DC, 3 A minimum (5 A recommended); DC out and USB-C on the saddle | 12 V DC, 5 A minimum, supply not included; DC and USB-C on the saddle | 12 V DC, 3 A minimum, 5 A recommended |
| Tripod or pier | 3/8 inch, M6 or TC40 connection | 85 mm base, 3/8-16 fixing; optional EMTC44 tripod or EMH150 pier | Not included; ZWO's TC40 carbon fibre tripod is sold with it as a set | Not included; ZWO's TC40 carbon fibre tripod is sold with it as a set | 3/8 inch thread and three M6 holes, as the ZWO AM5 |
| In the box | Mount, polar camera sticker, 1 m DC power cable, USB-C data cable, storage bag, manual | Mount; hand controller; Vixen/Losmandy saddle; mounting adapter; 0.5 m and 2 m USB 2.0 cables; soft bag | Head, hand controller with 2 m cable, travel case, 2 m USB-B and 1 m USB-C cables, performance sheet, quick guide, M6 Allen key; no counterweight bar | Head, foam carry case, handset with 2 m cable, 2 m USB-B and 1 m USB-C cables, counterweight bar (25 x 250 mm), periodic error test report, quick start guide, M6 hex key | The mount head only; no power supply |
In the hand
From the review video
Frames from my videos
The second group of four mounts guiding at the same time
My final table: the ST25 first at 0.66 arcsec
What would you put on it?
The ST25's 20 kg and 30 kg ratings under a rig you can change part by part, then the same rig on six other mounts
How well does it guide?
Seven mounts, eight rows, the same 50 mm guide scopes and ASI120 cameras on ASIAIR units, four targets on one night in my garden; the AM5N ran in both groups
“The 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.”
“As for the big boys, we are once again seeing some really good results, all producing sub 1 readings for their total RMS,... and the ClearSky ST25 having an absolute worldie.”
“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.”
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 ST25’s precise recorded tracking, and the moving traces are drawn to those figures, not replayed from the mount.
What is it for? In my words
Three things it is for
A power station in the head
The first thing that stood out was not the payload but the power station built into the head: a dew heater, a camera and whatever else all plug in at the mount.
A laser for the pole
Out of all of the mounts, the AM5N and EM31 Pro were the only ones I accurately polar aligned, because they are the only two in my showdown that don't have a laser pointer inbuilt. The laser allows me to very lazily polar align the mount, just eyeballing the North Star, Polaris, with the mount's inbuilt laser.
30 kg with a counterweight
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, but it's the design and additional accessories inbuilt that make it an absolute dream.
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 (Andromeda Galaxy)
- 7:49 Round 1 results
- 8:56 Big mounts (Heart Nebula)
- 10:57 Big mounts (North America Nebula)
- 12:46 Big mounts (Veil Nebula)
- 14:14 Final results
- 17:28 Conclusion
Transcript of the review video 3,817 words · 20 chapters · searchable
Press a time stamp to play from there.
0:00 Intro
0:00 Tonight's video may well be the greatest telescope mount review video on the planet. 0:07 And that's because I'm not going to be reviewing just one mount, I'm going to be reviewing seven telescope mounts at the same time, under the exact same conditions, with precisely the same guiding equipment. 0:17 This video has taken months of preparation to do, 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. 0:33 So let's find out what is the best pound for pound telescope mount on the market. 0:38 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. 0:55 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. 0:58 It is also very small and supposedly capable of payloads up to 20kg. 1:03 Oof. 1:03 Could this ST-17 mount be the answer to all of our prayers? 1:09 It's a budget-friendly mount that packs a punch and is available for under £500 before taxes and shipping. 1:13 Then we have one of my favourite mounts of the last few years, the JUWEI-14. 1:18 It's very well made, durable and has travelled with me a lot over the last 6 months. 1:22 I'm also a very big fan of the Swiss Army knife of strain-wave mounts, the EM31 Pro. 1:27 This is a strong rival to the AM5N, albeit with a lot more compatible accessories. 1:32 Speaking of which, here it is, arguably the most popular strain-wave mount series in history. 1:37 It is also the only mount feature today that is available via UK and US retailers. 1:41 And finally, the telescope mount equivalent of a unicorn. 1:46 This colossal beast of a mount seems too good to be true. 1:50 It ticks all of my boxes and even features additional USB and DC power ports. 1:55 how cool is that? 1:55 So we do have a huge variance in the mounts I'm going to be reviewing. 1:55 We have a £299 mount and we also have a £2199 mount. 2:00 My biggest justification for making this video is that I love these third-party AliExpress mounts because they're so affordable. 2:12 Astrophotography is an amazing hobby, I want more people to get into it, 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. 2:20 I don't want the go-to answer for what is the best beginner telescope mount to be, a £2,199 AM5N telescope mount. 2:25 That's not a K. 2:33 That basically rules out 99.999% of the population from taking an interest in this hobby. 2:38 Instead, I want to be telling people, hey, check out this £299 telescope mount. 2:38 Yes, it only carries payloads up to 5kg, 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 can 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 small mounts and the second part is going to be reviewing the very heavy mounts including the biggest telescope mount that I've ever tested. 3:08 Yeah that won't be really special. 3:08 Right so let's get stuck in with the small mounts and see how they fare.
3:10 Small mounts (Andromeda Galaxy)
3:12 So right now they're all looking at the Andromeda Galaxy and guiding at the exact same time and you can see the results displayed down here below. 3:20 I'm going to speed these up a little bit. 3:20 Every single one of them is guiding at one second long exposures and yeah all in all they're producing some very good results but perhaps most surprisingly out of these four tracker mounts the one that seems to be faring the best is the TeSeek 11. 3:33 Yeah not too sure what to think about that. 3:39 So the number we're going to be focusing on throughout this video is the total RMS value. 3:42 Much like in golf, the smallest score wins. 3:42 The highest number is, the more our mount is having to correct its position to remain focused on our target. 3:50 This means our chances of having pinpoint stars are going to reduce, especially if this value exceeds something like 2.00, which I've already noticed the JUWEI-14 and the AM5N mount do. 4:01 I am going to be testing these mounts out on 4 different targets, but for our first test, none of them fared particularly well on the Andromeda Galaxy, excluding the TeSeek 11, which has 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 thing I expected from such a lightweight and flimsy mount. 4:21 Now when I was filming this video, the goal was to analyse the log graphs recorded throughout these observations later on. 4:25 But for some very frustrating reason, only the ASIAIR Plus recorded this data, while the ASIAIR Mini recorded absolutely nothing. 4:34 So instead I've had to write a script that will analyse each individual frame of my screen recordings to determine what the total RMS value was over the course of these observations. 4:43 It will then calculate the average at the end to give me a good idea as to how the mount's guiding was overall. 4:47 And in the case of the TeSeek 11, it really doesn't get much better than that. 4:53 Seriously, should we just call it that? 4:53 That is flawless. 5:03 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 nitty-gritty details and explore the data in more depth something my fellow nerds will really enjoy 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 make sure you subscribe to my new channel The Telescope Man if you love astrophotography content and to give you an idea of what to expect here's a quick teaser Hello I'm the telescope man and I'm on a mission to review every single telescope on our planet.
5:31 Telescope Man trailer
5:37 My goal is to show you what our night sky really looks like through each and every single one of them. 5:41 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. 5:45 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. 5:54 I'm also going to be taking on the most famous space telescope in history from my light polluted English garden. 5:59 Is it possible for me to outdo the Hubble Space Telescope? 6:04 Let's find out. 6:04 I'm going to be posting daily stargazing videos every day right here 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. 6:26 I do test them out on the Andromeda Galaxy again in about 2 hours time but the results are very similar. 6:31 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 SQA55 in an ASI 533.
6:34 What is a good RMS?
6:41 This is a very wide field setup and as a result, an RMS of lower than 1.35 would be considered good. 6:47 But when you're using longer focal length setups with the same camera, your guiding needs to be much more precise, ideally under 1. 6:56 So now let's see how the bigger mounts get on when pointed at the same target 2 hours later.
7:00 Big mounts (Andromeda Galaxy)
7:01 Now we have the ClearSky ST17 Mini, the EM31 Pro, the ClearSky ST25 and once again the exact same ZWO AM5N mount. 7:08 This mount is acting as our control mount or our reference mount for both of the tests. 7:14 The first thing you can probably note is how absurdly long the the AM5N was taking to calibrate its guiding once again. 7:22 The tracking numbers seem to be a bit better across the board, possibly because the Andromeda Galaxy was higher in the sky, and possibly because these heavy mounts have the same payloads as the small 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 1 spot. 7:45 Okay, let's now find out where each test cut ranks in our first round of guiding results.
7:49 Round 1 results
7:50 And would you look at that! 7:51 I suspect this right here is why scientists for centuries have done repeat tests. 7:56 Because the cheapest and least sturdy mount of the bunch has ranked first in the guiding results. 8:01 Shockingly, the AM5N finishes both last and second last with its two attempts. 8:06 But the 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. 8:13 Will this prove to be a one off or can they keep this up? 8:16 Let's find out. 8:17 Right, let's move on to our next target which is the Heart Nebula.
8:18 Small mounts (Heart Nebula)
8:21 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. 8:29 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 but now the TeSeek 17 is crushing it with some insanely low numbers. 8:41 The JUWEI-14 is doing a decent job and the AM5N has improved slightly on its previous round but not by much. 8:48 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. 8:55 The bigger mounts tests were conducted later on than the small mounts with the Andromeda Galaxy and Heart Nebula being high in our night sky at this point and thus arguably easier to track.
8:56 Big mounts (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. 9:10 as you can see the second time around these are good readings it's just about keeping up with the other big boys with the em31 pro and clear sky st25 noticeably having strong rounds yet again where does that leave us in terms of rankings well when looking at the heart nebula it's another win for the t seek mounts this time the t seek 17 takes the golden medal as the t seek 11 swaps its gold medal for a red participation ribbon with a total rms of 1.47 Yeah, that first round of testing seemed a little too good to be true from the TeSeek 11.
9:21 Round 2 results
9:41 I think we all generally expect the cost of the mount to correspond to its performance, so it feels like things are back to normal now that the cheapest mount is last in our table.
9:48 Deeper dive: polar alignment?
9:49 I did a bit of a deeper dive on the AM5N's guiding results, particularly its worser set out of these two looking at the heart nebula. 9:55 And the odd part is that its results aren't down to a dodgy polar alignment. 9:59 In fact, its polar alignment is almost spot on. 10:01 And ironically, out of all of the mounts, the AM5N and EM31 Pro were the only ones I accurately Polar Aligned. 10:06 This is because they're the only two mounts featured in today's video that don't have a laser pointer inbuilt. 10:10 Which allows me to very lazily, I might say, Polar Align the mount. 10:16 Seriously, the method I use for Polar Aligning the AM5N is far more precise than this. 10:21 But it also takes a lot longer than just eyeballing the North Star Polaris with your mounts inbuilt laser. 10:26 Moving on to our next target, the North American Nebula, I'm expecting better results across the board.
10:28 Small mounts (North America Nebula)
10:31 This is because this stunning nebula is almost directly overhead at this point of the year and filled with plenty of decently bright stars making it great for guiding. 10:39 As you can see from these readings, all of the small mounts are performing very similar to one another, 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. 10:54 I think this round might belong to the AM5N which is performing much better.
10:57 Big mounts (North America Nebula)
10:58 As for the big boys, we are once again seeing some really good results, All producing sub 1 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 worldie. 11:13 And to be fair, the Clear Sky ST17 Mini would also be having a very good round if it wasn't for these peaks that keep boosting it's total reading numbers. 11:20 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.
11:31 Round 3 results
11:32 So, our results for the penultimate round are excellent across the board, with the TeSeek 11 the worst performer for the second round in a row, but hey, imagine being the worst performer with an average total RMS of 0.9, I would take that as my mount in a heartbeat. 11:47 The heaviest mount to clean up this round, with the AM5N making its first entry into our top 3, taking home a silver medal, and the ST25 and EM31 Pro making their way onto the podium yet again.
11:58 Small mounts (Veil Nebula)
11:59 and our final target is going to be the Veil Nebula. 12:02 So let's see how they fare up against this supernova remnant. 12:05 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. 12:14 Perhaps someone in the comments can highlight exactly what this might be. 12:17 I must emphasize that all of the mounts are using the exact same guiding scope, camera, guiding software, and imaging settings. 12:24 I discuss this point further in the extended edition of this video on my new channel, the telescope man. 12:30 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. 12:36 So in regards to the small mounts it looks like it's going to be sub 1 guiding results across the board yet again. 12:42 With the TeSeek 11 having yet another good round and the AM5N finally starting to look like a 2000lb telescope mount.
12:46 Big mounts (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. 13:03 The rest of the bunch seem to be producing solid numbers with the AM5N mount eventually giving readings that are almost identical to its scores in a small mounts test. 13:12 So it is proving to be consistent. 13:13 We'll now take a look at the final round of results before then crowning our winner.
13:17 Round 4 results
13:17 For the final round it's the EM31 Pro that takes gold. 13:21 The TeSeek 11 that sneaks into silver just ahead of the JUWEI-14 that claims its very first podium finish of the episode. 13:25 The less said about the clear sky st17 mini score the better. 13:31 So there we have it our tests have reached their conclusion there are a lot and I mean a lot of variables in tests like these. 13:36 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. 13:49 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. 13:57 Yeah testing four mounts at the same time was already messy enough I don't want to go through the stress of testing seven at the same time. 14:05 Alright it's time to find out our winner. 14:08 What is the best pound-for-pound telescope mount on the market?
14:14 Final results
14:14 In 8th place we have the AM5N with it's first set of test results. 14:23 Grouped in with our small mounts, a very underwhelming performance from this titan. 14:27 Followed by the ClearSky ST17 Mini in 7th place, I think it's clear to identify it's faults based on my readings, but even with that being said, an average total RMS of 1.09 for a 599 pound mount is nothing to be sniffed at. 14:41 Next up in 6th place is the AM5N again. 14:44 This time it is it's second set of results alongside the big boys, I mean at least this mount has proven to be consistent. 14:51 My beloved JUWEI-14 mount squeezes in just under 1 RMS and does exactly what it says on the tin, nothing special just gets the job done. 14:59 It's only real points deduction in the grand scheme of things is it's lower payload capacity which at 13kg with a counterweight is still a very large amount. 15:07 Hang on a second, look at this guy, 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? 15:19 Time will tell. 15:20 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. 15:29 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. 15:39 The EM31 Pro mount has lived up to its price tag by delivering some excellent results. 15:44 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. 15:54 And at 0.73 RMS I think you can safely say that they have delivered on that. 16:00 Finally in first place our golden medal winner is the absolute tank, the monstrosity, the ClearSky ST25 mount. 16:07 When I first saw the specifications of this mount saying that it can hold up to 30kg as its payload, I knew this was a mount that I had to have, but it's the design and additional accessories inbuilt that make it an absolute dream. 16:21 Before this video it ticked all of my boxes, but now seeing how well it guides, I mean it just defies belief. 16:27 A worthy winner of the title of best pound for pound telescope mount on the market.
16:32 Build your own astro rig
16:33 And if you want to help building your dream astro rig, then why not try out my brand new astro rig builder. 16:38 It's the first of its kind and allows you to set your budget and pick the exact gear that suits you best. 16:42 All of the equipment included is stuff that I've already reviewed on my channel and will happily vouch for. 16:47 This is the first version on my website so it will only get better from here on out. 16:51 There are buy now buttons which will take you straight to the items product page for further inspection 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. 17:06 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. 17:13 As I'm sure you can imagine this took a lot of time and effort for me to create from scratch 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 and share the web page with any fellow astro nerds who you think might also appreciate it. 17:25 Let me know what you thought of today's telescope mounts in the comments down below and And if you own any of these yourself, then please share your own personal experience for the rest of us astrophotographers to read and discuss.
17:28 Conclusion
17:38 Yeah, the more hands-on reviews we get of these unknown Tusker mounts 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. 17:48 I've been saying for a couple of years now that strainwave mounts are the best thing to happen to astrophotography in the last decade or so, and that's because they make it so much easier without having to lug around counterweights and sorts. 17:58 They're incredibly small and lightweight, And if we only have to pay 299 pounds for them, even better. 18:04 Thanks for watching, I'm Damon Scotting and this was Astronomical. 18:08 Don't forget to check out my new channel The Telescope Man 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. 18:16 Cheers!
Check out more videos on the ClearSky ST25
One of the BEST Mounts in the WORLD or Underwhelming...? (AM7 Review)
4 May 2026
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 ST25
0.66″ average, 1st of 8
94/100 Stars for Your Buck
| Target | Readings | Mean | Range | RA | DEC |
|---|---|---|---|---|---|
| Andromeda | 15 | 0.63″ | 0.29″ to 0.72″ | 0.46″ | 0.42″ |
| Heart | 10 | 0.70″ | 0.60″ to 0.81″ | 0.47″ | 0.52″ |
| North America | 9 | 0.51″ | 0.40″ to 0.61″ | 0.35″ | 0.36″ |
| Veil | 11 | 0.86″ | 0.71″ to 1.07″ | 0.63″ | 0.57″ |
Should you buy it?
94/100 Stars for Your Buck
Pros
- With a power station built into the head it is the Swiss Army knife of telescope mounts, and the first mount I saw on the market that offered one.
- “Before this video it ticked all of my boxes, but now seeing how well it guides, I mean it just defies belief.”
- It finds a mechanical home position, stops at mechanical limits and brakes both axes when the power is off.
- It runs OnStep over USB, Bluetooth, WiFi or ST-4, so an ASIAIR can drive it.
Cons
- The head alone weighs 8.5 kg: it is not a grab-and-go mount.
- No UK or US retailer stocks it: it ships from China through TeSeek's store and AliExpress, and returns go back to China at your cost.
- It needs 12 to 15 V at up to 5 A, so plan for a mains supply or a large battery.
A worthy winner of the title of best pound for pound telescope mount on the market.
Who the ST25 is for
Pier imager with a heavy refractor or SCT
Buy
It carries 20 kg without a counterweight and 30 kg with one on my card, on harmonic drives with brakes.
Guiding perfectionist
Buy
It had the lowest average of the eight rows in my showdown and the best North America Nebula round, 0.48 arcsec.
Imager tired of cables
Buy
Four 12 V outlets and four USB ports sit on the saddle, so the camera and the dew heater plug in at the mount.
Traveller
Skip
An 8.5 kg head is not a travel mount; my recommendation is the TeSeek 11.
Owner of a small refractor
Skip
My recommendation is the JUWEI-14: 8 kg without a counterweight for far less money.
Buyer who wants a local dealer
Skip
My recommendation is the ZWO AM5N, the showdown mount that UK and US retailers stock.
Three alternatives I have reviewed
- EM31 Pro Second in my showdown at 0.73 arcsec; 13 kg without a counterweight on my card 52/100 £1,679 Read the review
- ZWO AM7 ZWO's heavy harmonic mount: 20 kg without a counterweight and 30 kg with, on my card 58/100 £2,599 Read the review
- MLAstro SAL-33 15 kg without a counterweight and 20 kg with, on OnStep X 91/100 £937 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
Six questions, answered
Questions about the ClearSky ST25
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. Shop links marked Ad are affiliate links: I earn a commission when you buy through them, at no extra cost to you. How this site is funded
- How well does the ClearSky ST25 guide? It won my seven-mount showdown: 0.66 arcsec average total RMS over the Andromeda Galaxy, the Heart, the North America Nebula and the Veil, first of eight rows, with 0.48 on the North America Nebula. How well does it guide? ↓
- How much can the ClearSky ST25 carry? My own spec card says 20 kg without a counterweight and 30 kg with one, from an 8.5 kg head. ClearSky rate it 30 kg without counterweights, and TeSeek's listing says 30 to 35 kg. What would you put on it? ↓
- What power does the ClearSky ST25 need, and what can it power? 12 to 15 V at 2 to 5 A in. On the saddle are four 12 V 3 A DC outlets and four USB ports, so a camera and a dew heater can run from the mount. What is it for? In my words ↓
- Does the ClearSky ST25 work with an ASIAIR? Yes. It runs OnStep and connects to an ASIAIR by USB or WiFi; every mount in my showdown guided from an ASIAIR with the same 50 mm guide scope and camera. The specifications and the comparison table ↓
- Where can I buy the ClearSky ST25? From TeSeek's own store and on AliExpress, both shipping from China; I found no UK or US retailer. Both now list it as the ST25 Pro. The verdict, the readers and the sellers ↓
- ClearSky ST25 or ZWO AM5N? In my showdown the ST25 averaged 0.66 arcsec to the AM5N's 0.99 and 1.10. The AM5N is the lighter head at 5.5 kg on my card, and UK and US retailers stock it. How well does it guide? ↓