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Absolute encoders mount for remote OBS

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#1 AstroCatinfo

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Posted 14 September 2021 - 06:05 PM

I would like to ask for advice on which brand of mount should I get for a remote observatory (more than 8.000 km's away from home... so no possibility to go there and fix anything fro a while). I'm from Europe.

 

I'm a satisfied owner of a Mesu200 mount, but it does not include the absolute encoders that I'd love to have for a remote project...

 

Weight capacity: above 40kg

Budget: as low as possible (yes, I know it will be more than 10.000$, but as tight as possible)

 

 

Many thanks,

 

Aleix Roig


Edited by AstroCatinfo, 15 September 2021 - 02:18 PM.


#2 RazvanUnderStars

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Posted 14 September 2021 - 08:35 PM

To be honest, I don't think such a mount exists. You want:

  • a significant weight capacity
  • absolute encoders
  • mechanical, electrical and software reliability for running remotely without servicing
  • remote serviceability for software issues

but a price <$10K. One mount that satisfies the first three criteria is 10Micron's GM2000HPS (particularly suitable because you're in Europe) but unfortunately a GM2000HPS will be over your target price. 


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#3 rgsalinger

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Posted 14 September 2021 - 09:46 PM

The two options right around that price are a GM1000 from 10Micron or the AP Mach2 for about the same money here in the US, but 40 kg is a bit outside their capacity. I don't know why you think that you need absolute encoders, the real issue is overall reliability.

 

I've been using my Paramount MX+ for over 5 years now mostly remotely and never had a serious issue that required me to go out to the observatory that had anything to do with the mount itself. When I visit remote observatories here in the states I see plenty of Paramounts as well as AP mounts and a smattering of GM2000. 

 

Forty KG is a lot of weight.  I have a Planewave CDK 12.5 with all the trimmings plus a full frame mono camera on my MX+ and it all comes in at less than 35 kg for sure. 

 

Rgrds-Ross


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#4 dan_1984

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Posted 15 September 2021 - 12:13 AM

I would like to ask for advice on which brand of mount should I get for a remote observatory (more than 8.000 km's away from home... so no possibility to go there and fix anything fro a while). I'm from Europe.

 

I'm a satisfied owner of a Mesu200 mount, but it does not include the absolute encoders that I'd love to have for a remote project...

 

Weight capacity: above 40kg

Budget: as low as possible (yes, I know none less than 10.000$, but as tight as possible)

 

 

Many thanks,

 

Aleix Roig

I don't think there is mount with above 40 kg payload and absolute encoders, under 10.000$.

You should ask mr. Mesu how much a new Mesu 200 MKII with absolute encoders costs? Sitech already has PointXP for mount modeling, the same bit of software used by Planewave, so it's just a matter of adding the Renishaw AE to the Mesu.

I might be interested also, so if get a quota for a Mesu 200 with AE, do PM me smile.gif .  I am expecting double the cost around 10-12.000 EUR ...


Edited by dan_1984, 15 September 2021 - 12:17 AM.

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#5 rockstarbill

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Posted 15 September 2021 - 01:30 AM

Mach 2 will get you as close to 40kg as possible in that price range. It has 34kg of capacity vs 25kg of the 10um 1000.
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#6 dhaval

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Posted 15 September 2021 - 07:42 AM

The real question has to be - why a mount with encoders? What is your application? Just because it is remote does not mean you need an encoder mount.

 

That aside, if you still need an encoder mount that can hold 40kgs and is under $10K, you need to look for used mounts. The 10Micron GM2000 will fit the need and maybe you will get lucky. It does not hurt to post an ad here and on AM (or any other European sites). 

 

I would also be on the lookout for an AP1100 (most likely used, new ones are going to be backordered for a bit). The good thing with an AP1100 is that you can buy one with or without encoders. The wise thing to do would be to get an AP1100 without encoders so that you can test drive it and find out for yourself if you really need encoders. A lot of people, me included, have used AP mounts in remote locations without any encoders and they provide absolutely fantastic performance night after night. 

 

CS!


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#7 dan_1984

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Posted 15 September 2021 - 08:06 AM

The real question has to be - why a mount with encoders? What is your application? Just because it is remote does not mean you need an encoder mount.

 

That aside, if you still need an encoder mount that can hold 40kgs and is under $10K, you need to look for used mounts. The 10Micron GM2000 will fit the need and maybe you will get lucky. It does not hurt to post an ad here and on AM (or any other European sites). 

 

I would also be on the lookout for an AP1100 (most likely used, new ones are going to be backordered for a bit). The good thing with an AP1100 is that you can buy one with or without encoders. The wise thing to do would be to get an AP1100 without encoders so that you can test drive it and find out for yourself if you really need encoders. A lot of people, me included, have used AP mounts in remote locations without any encoders and they provide absolutely fantastic performance night after night. 

 

CS!

Why not a mount with encoders? What are the cons, I don't see any?


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#8 psandelle

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Posted 15 September 2021 - 10:12 AM

Why not a mount with encoders? What are the cons, I don't see any?

Probably just price.

 

Paul


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#9 rgsalinger

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Posted 15 September 2021 - 10:16 AM

The big "con" is around 5K in pricing when looking at the 40kg class. You can get an iOptron CEM120 for 5K. The encoder versions of that mount is now about 8K. And those aren't even absolute encoders. Last time I checked AP was charging around 5K for the encoders on the AP1100 or the AP1600 (I didn't look it up today.) The GM2000 costs about 5K more than my MX+ with roughly the same weight capacity. So, there's that to consider.

 

Since the OP wants to spend 10K use and have absolute encoders, the only way out to support a full 40kg is, as dhaval pointed out, a used mount.  Forty kg is one big system! Frankly, I can't imagine putting a system 8000km remotely from my house and expecting it to run without someone knowledgeable on site.

 

All of the observatory class mounts have a way of recovering from power outages, being moved when turned off, being bumped, etc. It's just that having absolute encoders is by far the most elegant solution. I use an enormous RC25 which has no clutches and requires two people to park it if there is no power. If it happens to stall or we have a power glitch, it is enormously reassuring that the renishaw encoders know exactly where the scope is pointing. I just tell it to "park" to make sure that all is well and then go back about my business. It's been this way since the encoders were installed 6 years ago. 

 

Rgrds-Ross


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#10 WadeH237

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Posted 15 September 2021 - 11:29 AM

Why not a mount with encoders? What are the cons, I don't see any?

If you have the budget, there are no cons.

 

I like to think about my budget in terms of "price to performance" or "price to results".  I have two Astro-Physics mounts, one with absolute encoders and one without.  The one with encoders is better than the other one, but not by much.  Both of them will track and guide better than my typical seeing.

 

The benefit to the encoder mount is that it has zero PE and zero declination backlash.  In a remote observatory setting (which is not my scenario), there is another benefit that the mount cannot get lost without loosening the clutches, which will not happen without something there to do that.

 

The PE and declination backlash are both easily addressed via PEMPro and proper guide settings.  The price of the encoders is quite steep to incrementally improve what is already an exceptional mount.


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#11 pmuller

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Posted 15 September 2021 - 12:38 PM

Not in the same league as AP/10m, but for the payload/price/encoders (RA only and much lower resolution AFAIK) you should consider the SW EQR-8 Rh. I have no experience with remote OBS but planning to go remote next year, from all the conversations I've had and everything I've read about I would not go this route.

AP Mach2 was suggested; however price is an unknown and waitlist is certainly over 12 months, most likely something between 18 and 24mths. On the 10Micron for your payload requirements you would have to pay $15k+ on the GM2k.

Edit: a lot of people in the USA use AP and SB mounts with no encoders as some suggested, will you have someone to manage or is it your own observatory with absolutely nobody to troubleshoot if necessary?


Edited by pmuller, 15 September 2021 - 12:41 PM.

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#12 DuncanM

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Posted 15 September 2021 - 12:58 PM

I would like to ask for advice on which brand of mount should I get for a remote observatory (more than 8.000 km's away from home... so no possibility to go there and fix anything fro a while). I'm from Europe.

 

I'm a satisfied owner of a Mesu200 mount, but it does not include the absolute encoders that I'd love to have for a remote project...

 

Weight capacity: above 40kg

Budget: as low as possible (yes, I know none less than 10.000$, but as tight as possible)

 

 

Many thanks,

 

Aleix Roig

For remote control you don't need absolute encoders, as long as the mount has the ability to find it's home or zero position with a zero position sensor. The CEM120, 120EC and 120EC2 should work as they are fitted with a zero position sensor.


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#13 rgsalinger

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Posted 15 September 2021 - 01:50 PM

My Paramount has never required someone to be in the observatory if it loses power or stalls or someone moves it while the power is off. All that I have to do is home the mount. It's the same with my CEM120EC2, I just search out zero. It is more elegant to have absolute encoders but any mount intended for remote use has features that will recover the mount if it is lost as far as I know. (I'm not sure about the big Celestron or Meade mounts.)


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#14 AstroCatinfo

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Posted 15 September 2021 - 02:03 PM

Maybe I did not write it well: more than 10k, of course… Sorry for the misunderstood.

 

To be honest, I don't think such a mount exists. You want:

  • a significant weight capacity
  • absolute encoders
  • mechanical, electrical and software reliability for running remotely without servicing
  • remote serviceability for software issues

but a price <$10K. One mount that satisfies the first three criteria is 10Micron's GM2000HPS (particularly suitable because you're in Europe) but unfortunately a GM2000HPS will be over your target price. 


Edited by AstroCatinfo, 15 September 2021 - 02:29 PM.


#15 AstroCatinfo

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Posted 15 September 2021 - 02:07 PM

Thanks for your comments. Maybe I could reduce the weight capacity requirement. I was just being flexible in order not to have to replace it in a future if I want to install another scope. Right now I will be using a dual FSQ106 setup.
 

The two options right around that price are a GM1000 from 10Micron or the AP Mach2 for about the same money here in the US, but 40 kg is a bit outside their capacity. I don't know why you think that you need absolute encoders, the real issue is overall reliability.

 

I've been using my Paramount MX+ for over 5 years now mostly remotely and never had a serious issue that required me to go out to the observatory that had anything to do with the mount itself. When I visit remote observatories here in the states I see plenty of Paramounts as well as AP mounts and a smattering of GM2000. 

 

Forty KG is a lot of weight.  I have a Planewave CDK 12.5 with all the trimmings plus a full frame mono camera on my MX+ and it all comes in at less than 35 kg for sure. 

 

Rgrds-Ross



#16 AstroCatinfo

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Posted 15 September 2021 - 02:11 PM

My main concern is that I don’t want to get the mount lost even if there’s an electric cut or any other problem… 

 

 

The real question has to be - why a mount with encoders? What is your application? Just because it is remote does not mean you need an encoder mount.

 

That aside, if you still need an encoder mount that can hold 40kgs and is under $10K, you need to look for used mounts. The 10Micron GM2000 will fit the need and maybe you will get lucky. It does not hurt to post an ad here and on AM (or any other European sites). 

 

I would also be on the lookout for an AP1100 (most likely used, new ones are going to be backordered for a bit). The good thing with an AP1100 is that you can buy one with or without encoders. The wise thing to do would be to get an AP1100 without encoders so that you can test drive it and find out for yourself if you really need encoders. A lot of people, me included, have used AP mounts in remote locations without any encoders and they provide absolutely fantastic performance night after night. 

 

CS!



#17 AstroCatinfo

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Posted 15 September 2021 - 02:14 PM

Yes, I have an engineer there taking care of the observatory…

 

Thanks for your thoughts!

The big "con" is around 5K in pricing when looking at the 40kg class. You can get an iOptron CEM120 for 5K. The encoder versions of that mount is now about 8K. And those aren't even absolute encoders. Last time I checked AP was charging around 5K for the encoders on the AP1100 or the AP1600 (I didn't look it up today.) The GM2000 costs about 5K more than my MX+ with roughly the same weight capacity. So, there's that to consider.

 

Since the OP wants to spend 10K use and have absolute encoders, the only way out to support a full 40kg is, as dhaval pointed out, a used mount.  Forty kg is one big system! Frankly, I can't imagine putting a system 8000km remotely from my house and expecting it to run without someone knowledgeable on site.

 

All of the observatory class mounts have a way of recovering from power outages, being moved when turned off, being bumped, etc. It's just that having absolute encoders is by far the most elegant solution. I use an enormous RC25 which has no clutches and requires two people to park it if there is no power. If it happens to stall or we have a power glitch, it is enormously reassuring that the renishaw encoders know exactly where the scope is pointing. I just tell it to "park" to make sure that all is well and then go back about my business. It's been this way since the encoders were installed 6 years ago. 

 

Rgrds-Ross



#18 AstroCatinfo

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Posted 15 September 2021 - 02:17 PM

EQ8 is out of my scenario… I plan to soend the budget in a top class observatory mount with absolute encoders. Being european I see the 10Micron a great option! Here the AP are very expensive, and I guess are not better than 10Micron.

 

Many thanks!!

 

Not in the same league as AP/10m, but for the payload/price/encoders (RA only and much lower resolution AFAIK) you should consider the SW EQR-8 Rh. I have no experience with remote OBS but planning to go remote next year, from all the conversations I've had and everything I've read about I would not go this route.

AP Mach2 was suggested; however price is an unknown and waitlist is certainly over 12 months, most likely something between 18 and 24mths. On the 10Micron for your payload requirements you would have to pay $15k+ on the GM2k.

Edit: a lot of people in the USA use AP and SB mounts with no encoders as some suggested, will you have someone to manage or is it your own observatory with absolutely nobody to troubleshoot if necessary?



#19 pmuller

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Posted 15 September 2021 - 02:19 PM

EQ8 is out of my scenario… I plan to soend the budget in a top class observatory mount with absolute encoders. Being european I see the 10Micron a great option! Here the AP are very expensive, and I guess are not better than 10Micron.

 

Many thanks!!

Then I'd go GM2000 all the way!


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#20 AstroCatinfo

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Posted 15 September 2021 - 02:21 PM

Is that option included in the hardware of the mount (controllers)? Do you think my Mesu200 could have that feature (Sithech controller).

 

Thanks!

My Paramount has never required someone to be in the observatory if it loses power or stalls or someone moves it while the power is off. All that I have to do is home the mount. It's the same with my CEM120EC2, I just search out zero. It is more elegant to have absolute encoders but any mount intended for remote use has features that will recover the mount if it is lost as far as I know. (I'm not sure about the big Celestron or Meade mounts.)



#21 AstroCatinfo

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Posted 15 September 2021 - 02:22 PM

Yes! The GM2000 is my first option. Thanks for your feedback.

 

 

Then I'd go GM2000 all the way!


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#22 rgsalinger

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Posted 15 September 2021 - 02:25 PM

I use SiTech on a custom built mount with absolute encoders. I have no idea about Mesu mounts but if there are no absolute encoders, then the mount needs a set of homing sensors to avoid having to be manually repositioned to a specific park position under some use cases. I'm sure that there's a Mesu forum where that could be answered. I'd be leery of putting any mount remote of a brand that was not already there. 


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#23 dhaval

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Posted 15 September 2021 - 02:27 PM

My main concern is that I don’t want to get the mount lost even if there’s an electric cut or any other problem… 

With APCC Pro, your mount be lost. I have tested that functionality extensively.

 

CS!


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#24 rgsalinger

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Posted 15 September 2021 - 02:35 PM

Others have posted over and over again that there's some circuitry in the AP CP controllers that keeps track of the mount. So, I thought that if the software was coded to "Resume From Last Park Position" and it stalled / lost power then could just be restarted. 

 

A Paramount can get lost but recovery of the mount is 100 percent certain even if you power it off and move it around. You just home the mount when the power comes back and you're good to go.

 

It's really hard to imagine that all the AP mounts in remote observatories don't have an equivalent facility. 

 

Rgrds-Ross


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#25 rockstarbill

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Posted 15 September 2021 - 02:42 PM

With APCC Pro, your mount be lost. I have tested that functionality extensively.

 

CS!

I am guessing this is a typo and you meant to say "your mount won't be lost". Confirm?

 

Others have posted over and over again that there's some circuitry in the AP CP controllers that keeps track of the mount. So, I thought that if the software was coded to "Resume From Last Park Position" and it stalled / lost power then could just be restarted. 

 

A Paramount can get lost but recovery of the mount is 100 percent certain even if you power it off and move it around. You just home the mount when the power comes back and you're good to go.

 

It's really hard to imagine that all the AP mounts in remote observatories don't have an equivalent facility. 

 

Rgrds-Ross

There is brownout protection. The servo controller will store its current position even in the event of a power failure. Once power is restored, the mount knows exactly where it is pointed. No need to home or park the mount at all. This is not dependent on APCC at all either. It is done by the controller.

 

What is difficult about the AP mounts, is correcting misinformation. The mounts themselves work as AP designed them. :) 


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