The 10Micron GM2000HPS II

[perfrej]

10Micron GM2000HPS version II

So, I upgraded my mount from an early version GM2000HPS to the revised model II version because I felt like it and got a good upgrade deal. Was it worth it?

The 10Micron mounts of today all feature proprietary absolute encoders with more than 10 million ticks per revolution; this is in addition to the normal encoders that always sit on the servo motors themselves.

The GM2000HPS, where HPS stands for “High Precision and Speed”, are very nicely built in Italy with very tight tolerances and good mechanical design. They also look very nice – whatever that is worth. I previously reviewed my original GM2000HPS so this review can focus on the differences.

Appearance

They changed the base of the mount to a slightly more modern looking one which may or may not be more stable. The stability was never an issue with the old one so there is no surprise here apart from the looks.

The motor covers are more integrated into the design and do not stick out in the same way as the old ones. This is a definite improvement in that cables do not snag should they be hanging a bit wildly around the mount. Like the base, the covers also look very nice with perfect black finish.

While we’re on the subject of finish; the mounts from 10Micron are all black nowadays, and they appear to have a very scratch resistant powder paint applied to them. It turns out that this is not the case. Instead of actually being painted, they are anodized in some mystical way in a process that is extremely sensitive to timing. The result looks like powder paint but is much, much more scratch resistant. The feature is not new to the version II mounts.

In addition to the base and the motor covers, there are minor changes to the look of the head, and apparently there are some changes inside as well.

Cabling and control box

The first generation GM2000HPS used one motor cable for each axis and one cable for the encoders. The control box was to be had in either a round model that fit as a pier extension, or in a square box that I believe originated in the GM4000 design (QCI and HPS) where there is a holder for it on the base. The generation II comes with a slightly smaller square box, a design that will be used on all the GM series mounts, GM1000HPS, GM2000HPS II, GM3000HPS and GM4000HPS II. The computer in the new box is more than twice as fast as the one in my old GM2000HPS; an improvement I thank them for.

The cabling has changed. The GM1000HPS comes with a single cable between the box and the mount, as does the GM3000HPS. The revision II of GM2000HPS has the same concept, and I think you will see it on the GM4000HPS revision II as well. It is a much better solution, but unfortunately the cable is a bit on the short side, just like the one supplied with the GM1000HPS.

I ordered a longer cable from Baader Planetarium – 2.5m – and am very pleased with that. Currently, that cable sits in my balcony setup with the GM1000HPS. The short one is used on the GM2000HPS II, which by the way is in our remote observatory in Provence (Olly Penrice’s premises).

Cabling between box and he rest of the world is unchanged, with one cable for 24V supply, one for network, one for remote on/off switching and a few extra connectors: two serial ports, guiding port (ST4) and an Aux. As usual, a Baader dome can be directly controlled and slaved from the mount control box with no additional software needed – it even handles all the geometry for the slaving. Also, one of the serial ports is in an RJ-11 connector that has direct GPS capability.

Internals

The motors are now the same all across the GM HPS range. Small but very capable servo motors with very aggressive control manage to swing the full instrument load (50kg imaging) around at a whopping 20°/s. I have mine set to the arbitrary number 14°/s in order not to scare Olly’s guests.

GM2000HPS of the old version used different motors and had a single belt between the motor and the worm gear. The revision II model uses the same dual belt with intermediate moving wheel as the GM1000HPS and the GM3000HPS. With covers off there is very little movement of the intermediate wheel allowed, but I believe it serves as a tension damper and thus makes the system robust and tight. They run with less noise than the old version and I would not hesitate to call it a very quiet mount, at least when comparing to all other mounts I have been in contact with. It is only at very high slew speeds that you actually notice that it is doing something wild.

In terms of control of the mount as a whole, not much has changed. The absolute encoders are in the main control loop, so wind and other external factors are dampened automatically. Periodic error is also reduced to just about zero as the actual resultant movement of the final output axis is in the control loop.

Performance

How does it measure up? I’d say “without surprises”. The old GM2000HPS always gave me unguided performance with up to one-hour subs, and the new one is about the same. Maybe it will turn out better, but so far it has performed according to spec, which in this class of mounts means unguided imaging out of the box with very few lost subs.

Modeling of the sky and compensation for atmospheric refraction is, as is the norm with all HPS mounts, handled directly by the control box without the need for an external computer. All HPS (and QCI) models share the same firmware package, but each model has separate handling of various parameters inside the firmware bundle. Hence, a firmware bug may affect only one model in the group. Dual axis tracking is also the same as the old model so no surprises there.

My first run with the new mount was simple and after initial polar alignment I ran a 45-point model and set ACP to image NGC6888 in Ha and O3 as a test. The results were good, but with a proper modeling I have since reached even better performance. Stars were round up to the maximum sub length that I tried (20 minutes) with my TEC-140 (FL 980mm). I had to throw a few subs away due to star trailing, but that is the kind of thing that stopped bugging me once I got a good model.

Conclusion so far

A wonderful and exciting mount that in a few areas over-shine the older model. In straight results there are no big changes, but it uses less power than the old model, is a bit more quiet, has a much faster control box and is simply a bit nicer. In addition, the new hand controller is nice with better buttons and a larger display.

/per

[Tinker1947]

Thats a very nice and sturdy looking Mount, my Bandsaw came from Italy and that's very good at what it does.........

[perfrej]

If I set it to 20 degrees per second slew rate and mount a saw-blade I could very well compete with you

/per

[Earl]

Im curious Per can you guide normally with these mounts?

They are very nice and unguided is cool, but is it not still guiding but just in a non optical way but what a mathematical calculated way?

[gingergeek]

Very nice indeed Per and that TEC 140 sitting on top completes it !

[perfrej]

Thanks, Ginger

Yes Earl, in a sense it is guiding, but blindly so. And yes again, they take ST4 and ASCOM Pulseguide, so no problems there. Question is why we would want to guide it... I have posted this one before, but here is a sample of a sub (one of six) with an exposure time of one hour. Many mounts cannot even do this with guiding. The target is M106, the mount my old GM2000HPS and the scope a Skywatcher 190MN. Single sub OSC (M26C), no processing but an auto-strech...

[Earl]

Its nice to have all that versatility at your finger tips.

I have yet to push my PA and guiding beyond 20 mins, its probably worth a try with Ha but i imagine with the glow from Ledbury (local town, as I image over it due to thats my best horizion although i am shielded by an interveening hill).

[perfrej]

That sub was shot with considerable polar alignment error

/p

[PeterWar]

Perhaps the GM3000 is a bit of an overkill, Maybe I could safe some money and buy the 10Micron GM2000 HPSII instead?

The weight of the Meade 16" F8 OTA is 70lbs (31,8kg) and the GM2000 HPS is rated for a max weight of 110lbs (50Kg).

Without an OAG, I would only need to add the weight of the dew shield, the spacers, the optec 3" temperature compensating focuser and focal reducer and the Moravian G2-3200 camera.

 

What do you think guys?

 

EDIT:Sorry, wrong thread!

[Fukinagashi]

Hi as I'm considering buying a GM2000 HPS (2013) I would like to know if it's possible to upgrade to the HPSII version and how much does it cost approximately.

Thanks!

[Davey-T]

1 hour ago, Fukinagashi said:

Hi as I'm considering buying a GM2000 HPS (2013) I would like to know if it's possible to upgrade to the HPSII version and how much does it cost approximately.

Thanks!

May be better off enquiring on the 10 Micron forum though not sure if you can join it without actually having a 10Micron mount ?

Dave

[Fukinagashi]

I've called 10Micron and they say no.

Thank you anyway!

[Synchronicity]

On 30/05/2015 at 17:07, perfrej said:

Thanks, Ginger

Yes Earl, in a sense it is guiding, but blindly so. And yes again, they take ST4 and ASCOM Pulseguide, so no problems there. Question is why we would want to guide it... I have posted this one before, but here is a sample of a sub (one of six) with an exposure time of one hour. Many mounts cannot even do this with guiding. The target is M106, the mount my old GM2000HPS and the scope a Skywatcher 190MN. Single sub OSC (M26C), no processing but an auto-strech...



Hi

There doesn't seem to be a file attached?

Michael

[Davey-T]

3 minutes ago, Synchronicity said:

Hi

There doesn't seem to be a file attached?

Michael

Very old post and sadly Per is no longer with us having passed away at a very young age.

Dave

[Synchronicity]

Hi Dave

Sorry, I hadn't even noticed the dates, apologies to all for my unintended insensitivity.

Michael