EQ Mount Tuning 101

11 October 2016 - 10 Comments

Posted by David Woods

We've all seen those pretty pictures - Hubble like images of Galaxies and Planets and I was struggling to get beyond 90 secs with my existing CG5-GT mount. I was always attracted to those images that had the greatest detail, but the signal to noise ratio improves by taking a number of longer exposures. Some expert astro-imagers were able to guide their long refractors at 15 - 30 minutes for each frame. How did they do that? Some of them had taken years to perfect their skill, while others had simply thrown money at it. So if you don't have time or money - what do you do? In essence I guess that this was how mount tuning was born. The lower end mounts are based on an older equatorial design, dating back over 40 years.

Over time worm drives and motors were added. But when astro photography started taking off in the late 1990's (I'm talking CCD here) then the pressure was being applied by this fast moving technology to improve the mounts. Since the last decade there has been a gold rush of new mounts and telescopes as well as software to exploit the night sky. However, equatorial mounts are not easy or cheap to produce, even in great numbers. It's always been the case that mounts and telescopes were bespoke, but mass production brought down prices and there are probably more people in astronomy now than in any point in history. But the expectation of what a £250 set up can (and needs to) do is high. So when you've spent £750 to £1000 on a mount then you want it to perform well. They do, but as the DSLR's and CCD's have become more clever the humble computerised mount, in terms of Sky-Watcher at least, is largely being propped up by EQMOD. As optics improved and triplet refractors are also coming down in price then imaging pushes ever deeper into the night sky.

For deep sky objects you need to expose longer to record more photons of light, but some of these mounts are over a decade old in design. Back then it wasn't possible to image as well as we do now. The whole industry is built on you constantly upgrading your mount every few years. To be frank, it's unsustainable, wasteful and expensive - and you're picking up the tab. Beyond an AZEQ6GT your next move would have to be of the EQ8/CEM60/CGEM variety. If you're starting out with an EQ6 it's an even bigger jump, and in both cases you'll lose at least a third or a half of it's value, when you upgrade.

The promise of a more expensive mount is that it can handle greater payloads and has improved accuracy. All of this is true, except for if you don't need extra payload, then what about accuracy?

Astro-Baby's HEQ5 and EQ6 strip downs are tried and tested ways of rejuvenating your mount. And then came along belt drive. This virtually eliminates backlash one of the biggest bugbears of these mounts. High end EQ mounts had been using this for years but, at a price. The Rowan Astronomy Belt Drive Kit is the single biggest upgrade you can make to an HEQ5 or EQ6. But what we also found is that by changing some components and experimenting with better lubricants and build, we could improve their performance even further. Our Reference Mounts have been key in these developments. You can should check out the difference made just by belt-driving by having a look at out my Mount Performance Charts blog.

If you look at the more expensive mounts they are no doubt, beautifully engineered. You could do the same thing with a cheaper mount yet it would still cost thousands, in terms of development and engineering. There are no shortcuts. This is a precise movement, like a Swiss watch. When you're guiding to a quarter of a pixel over a 2 metre focal length or more, you need to fully understand what you're attempting to do with a mount. This is like trying to make a watch more accurate - just scaled up.

Owning a tuned mount means you can concentrate on squeezing as much time out of your cameras and telescopes as possible. More importantly you can do it with confidence. You may have discovered by reading our testimonials page that by accident or design, our customers have found that their mounts perform to a much higher standard and push themselves harder to get longer exposures. That's great - but the whole point of this exercise is that you spend less time fussing over your guiding and more time taking images.

But like overclocking a computer, you can push a mount past its physical engineered limits, which comes with with a price. Usually this results in worse performance, even failure. Yes, you could tune a mount yourself but if incorrectly done, it won't be running at its full potential, could wear faster, or damage components over time. Our future efforts are now focused on providing longevity of this performance, now that we have attained consistent improved tracking.

Take the NEQ6. It has a 25Kg payload or circa 18Kg for imaging, and about 15-20+ arcsecs Peak-to-Peak unguided from factory spec. Tuning any mount will only improve it to it's mechanical limit, and not beyond. So while it's possible to guide a full 25Kg payload, the trick is to do it reliably as you would with a lighter payload. Balance is therefore critical, and that why for years we have been almost indoctrinated with upgrading our mounts to bigger ones, to ensure we have enough payload headroom.

Early Hyper-tuned GEN 1 NEQ6 mount with Belt-Drive Kit (Build Type: v6.9.3)

Our customers are finding that our hypertuned mounts can run full payloads not only for longer, but maintain sub-arcsecond accuracy, over and above a home-tuned mount of the same type. We have customers running full payloads over thirty minutes across all our tuned Sky-watcher EQ mounts. Oh, our Generation 2 Hypertuned NEQ6 now all run circa 3.5 arcsec RMS natively (circa less than 10-12 arc-secs Peak-Peak) and less than 0.5 arcsec guided. This is at 30 minutes subs from all our mounts at full payload when properly balanced. Our new Bonneville Build Type v6.3.x is aiming for even better figures, a flatter PHD line, and reduced Peak-to-Peak pattern. Best of all it provides a 2 year limited warranty, an industry first for aftermarket servicing.

So, if you don't need more payload but want to use all you have, then the evidence is stacking up that tuning really does save you money by extending the performance and lifespan of your mount.

Leave a reply

Optional, for replies

Your Comments

David Harvey 17 November 2016

hi Dave .. how much would I need to save up (guideline) to get my humble EQ5 serviced and tuned in the new year.

Dave 17 November 2016

Hi David, I'm just about to launch hypertuning for the SynScan EQ3-2 and EQ5 very shortly. Testing indicates like the Star Adventurer, that they will all run circa 1.5 arc-seconds, and about 23-30 arc-seconds unguided once I've dialled out the backlash after rebuilding the mount, which does is circa 1 arc-minute stock. As we develop this, like we have one the HEQ5/NEQ6, the unguided performance should improve. Price will be 189 including replacement worm-gear bearings. What Telescope are you using with your EQ5 and what issues are you having, if any?

Dave Harvey 18 November 2016

I'm using a SW 200p - the mount hasn't been used that often from new - dozen times or so.. it works fine but I have noticed a distinct 3/16th movement if you put pressure on the RA. of course with the OTA loaded this 3/16 - 1/8 movement through the eyepiece is flippin dramatic. I did take the motors off, took off the head and re-greased the worm drive etc with proper "red" bike grease. Most people on the forums say - yeh they all do that -

Dave 18 November 2016

I can make the mount tauter by removing the backlash in the worm-gears and drive gears, but to be honest the EQ5 is on the limit with a 200P, it's better with a 150PDS or ED80. Balance is key Red Bike Grease has a shorter lifespan, and contaminates easily, which is why it shouldn't be used. We get a lot of mounts in with black sludge, which was red grease. Just like on your bike, it doesn't last years. Teflon based grease also breaks down over time and white lithium will do the same, with cheaper varieties drying out.

allen456@hotmail.com 08 November 2019

Have you worked on the Celestron CGX?

Kenneth McQuillan 27 September 2021

I would like to book my Skywatcher eq5 mount for hypertuning my scope is altair starwave ascent 80 ED Altair starwave 60 guide scope guide camera altair 290c Pegasus focus Cube imaging camera 550D 3 years ago I bought the basic Skywatcher eq5 mount I later bought synscan upgrade kit I fit it myself it is quite noisey I accidentally bent one of my latitude bolts can you book me in for November how long will it take can you give details the full price including pickup and delivery

Michael 24 February 2019

Hello, I am looking to get into astro photography. I am buying an svx80t-3sv and an eq6r pro. I know this is going to be an awesome rig. I am on disability and I am looking to the future for a solid upgrade path. In the future I am going to want to add an 8" edge hd ota from celestron. I am understanding this is not a great setup on the eq6r pro. Will this hypertuning make the eq6r pro a solid machine for the edge 8 hd? I am trying to find realistic expectations and do not want to have to buy another mount later on. Looking forward to your reply.

Dave B 05 February 2017

Hi as a matter of interest how much would an EQ6 pro, be to have the belt mod and tuned .

admin 05 February 2017

The most popular tuning option is our EQ6 Pro Gen2 with Hybrid Ceramic bearings. This works out at 499. This improves on the stock mount and is at least twice as good as attempting to install the belt mod yourself. Customer supplied Periodic Error data proves it has reduced to just 8 arc-seconds which is great for unguided astro-imaging for up to 5-10mins with an 80mm Refractor, for example. The greases we use are 2.50 a gram and OEM Calibrated and Indexed and they transform the feel and responsiveness of the mount. There are cheaper options, but to date, no one has ordered them since the Generation 2 was launched last year! It also comes with a two warranty on the work carried out including components and PHD2 support to help you get the most out of the mount. Hope this helps, Dave

David Burlington 06 February 2017

Thanks

Modal Dialog Title