Topics

EXOS2 PMC-Eight #EXOS2

Saif
 

HI and hope you are all having a nice holiday. I'm in the UK and looking to purchase one of these mounts around the £600 budget. It seems the EXOS2 is the more silent compared to the iEXOS 100. A few thoughts and concerns.

1. Motor failure issues and how to immediately test the mount after purchase.
2. Polar align and if there are clutches to freely move the mount to do that.
3. PEC and Tracking accuracy issues and how to test. I understand there is no PEC system on the mount.
4. Software control of movement and if there is a software hand control.
5, Do the UK suppliers have an RMA procedure with ES in US?

 

Welcome, Saif!
 
Re: Silence/noise between the mounts.
These two mounts use the same motors, pulleys, and belts.  Same power train.  I have an EXOS2 PMC8, and while I can certainly hear the motors whirring when it slews, it's neither loud nor objectionable, and tracking is silent.  We have had some folks, with either mount, report noise problems and any of those that I remember, turned out to be from gear adjustment problems (binding).  Fix the adjustment, and the problem's solved.  The mounts use a belt drive, and there are not a lot of moving parts...
 
Re: Motor failures.  
Failures of the motors or PMC8 board would be extremely rare, but to test, hook it up to your control software and take it for a spin.
 
Re: Polar align
For polar alignment on the EXOS2, you need alt/az ajustment controls, not clutcheds, and the EXOS2 has those. There are clutches on RA and DEC mount axes, but you'd only use those for balancing your scope.  While there is a polar scope, I doubt many use it.  There are smartphone apps that are better and more convenient for visual users, and if you're doing astrophotography, there are other options that are more precise.
 
Re: PEC and Tracking accuracy issues and how to test
No, there's no PEC.  I think Jerry surprised people by positioning PEC as not being necessary with this mount, but it's true.  It's important to note that this mount should be used unguided for visual, and guided for astrophotography.  When guided, the combination of the PMC8's speed, and the simplicity of the power train, means that a well-adjusted mount can easily guide around the worm's periodic error.  My mount is well-adjusted and if I do my part to manage performance, I find that 5 and even 10 minute exposures can be reliably achieved.  Remarkable at this price point.
 
Re: Software control
No, there is no hand control.  If you value flexibility, this is a feature, not a bug.  The mount can be controlled wirelessly (usually for visual), or wired (usually for astrophotography).  The control program might be ES's "Explorestars", probably on a tablet, for visual, or ASCOM or INDI (usually for astrophotography). With ASCOM or INDI a variety of control programs can be used to manage the mount.  ASCOM runs on Windows (a laptop, tablet, or stick), and INDI runs pretty much anywhere linux runs.
This flexibility can catch people unawares, if they are expecting an only-one-way-to-do-it model.  My advice to you on this is to think about how you intend to use the mount, post a use case or two, and ask for recommendations of the easiest/best hardware/software stack to accomplish that. You'll probably end up in a longish thread, but that's ok.  Best to get clear of how you'll control the mount early-on.  If you intend visual, it might be as simple as wireless and a tablet or laptop you already have.
 
Re: UK RMA 
I wouldn't know about how service is delivered in the UK.  The ES folks will have to chime in on that, and this is New Years Eve, so it might be a day or two. 
 
Finally...
 
Here's a link to ES's software-and-download page.  The software isn't important at this stage, but there are links that will take you to docs, FAQ's, Knowledge Base, etc.  Lots of grist for the mill.

--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Saif
 


Thanks for your helpful links and advice Rob.

This mount seems to be a fine balance of bare necessities, keeping the costs down while doing away with time waste chores of astrophotography. Presumably from what has been said by others about pointing accuracy the EXOS2 is not a mount for touring the messier catalogue.

As for my aims the main requirements are:
Low noise
Portable
Manoeuvrable (software wise)
Expandable.

Everywhere I've lived has so far posed a challenge for astronomy and in my current house I probably wont see Polaris on my back porch. Garden faces the western sky and trees loom above if I go down to garden.

Hence I'm interested in alternative alignment methods. It would be very convenient if that 75 to 80cm wide strip of porch could be my work area. Saves going up and down steps to garden in the dark and loose wifi.

The possibility of a small balance shaft and small tripod base would be ideal.
Any idea if the shaft is a vixen standard screw on?

My equipment so far is a QHY guider, Skywatcher ED80 OTA and a Samsung NX500 dslr.
I expect to learn the configuration of Stelarium and Astrophotography Tools with ASCOM in due course.
Look forward to learn lots from the members here.

Thanks again for your welcome and help so far.

Saif

Tue, Dec 31, 2019 at 04:36 PM, Robert Hoskin wrote:

Welcome, Saif!
 
Re: Silence/noise between the mounts.
These two mounts use the same motors, pulleys, and belts.  Same power train.  I have an EXOS2 PMC8, and while I can certainly hear the motors whirring when it slews, it's neither loud nor objectionable, and tracking is silent.  We have had some folks, with either mount, report noise problems and any of those that I remember, turned out to be from gear adjustment problems (binding).  Fix the adjustment, and the problem's solved.  The mounts use a belt drive, and there are not a lot of moving parts...
 
Re: Motor failures.  
Failures of the motors or PMC8 board would be extremely rare, but to test, hook it up to your control software and take it for a spin.
 
Re: Polar align
For polar alignment on the EXOS2, you need alt/az ajustment controls, not clutcheds, and the EXOS2 has those. There are clutches on RA and DEC mount axes, but you'd only use those for balancing your scope.  While there is a polar scope, I doubt many use it.  There are smartphone apps that are better and more convenient for visual users, and if you're doing astrophotography, there are other options that are more precise.
 
Re: PEC and Tracking accuracy issues and how to test
No, there's no PEC.  I think Jerry surprised people by positioning PEC as not being necessary with this mount, but it's true.  It's important to note that this mount should be used unguided for visual, and guided for astrophotography.  When guided, the combination of the PMC8's speed, and the simplicity of the power train, means that a well-adjusted mount can easily guide around the worm's periodic error.  My mount is well-adjusted and if I do my part to manage performance, I find that 5 and even 10 minute exposures can be reliably achieved.  Remarkable at this price point.
 
Re: Software control
No, there is no hand control.  If you value flexibility, this is a feature, not a bug.  The mount can be controlled wirelessly (usually for visual), or wired (usually for astrophotography).  The control program might be ES's "Explorestars", probably on a tablet, for visual, or ASCOM or INDI (usually for astrophotography). With ASCOM or INDI a variety of control programs can be used to manage the mount.  ASCOM runs on Windows (a laptop, tablet, or stick), and INDI runs pretty much anywhere linux runs.
This flexibility can catch people unawares, if they are expecting an only-one-way-to-do-it model.  My advice to you on this is to think about how you intend to use the mount, post a use case or two, and ask for recommendations of the easiest/best hardware/software stack to accomplish that. You'll probably end up in a longish thread, but that's ok.  Best to get clear of how you'll control the mount early-on.  If you intend visual, it might be as simple as wireless and a tablet or laptop you already have.
 
Re: UK RMA 
I wouldn't know about how service is delivered in the UK.  The ES folks will have to chime in on that, and this is New Years Eve, so it might be a day or two. 
 
Finally...
 
Here's a link to ES's software-and-download page.  The software isn't important at this stage, but there are links that will take you to docs, FAQ's, Knowledge Base, etc.  Lots of grist for the mill.

--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

 

 

Saif,
 
Should be ok for all four reqts you list, although it depends on what you mean by expandable.  Can the mount carry a variety of loads?  Yes.  I'm sort of midrange (102/621mm, about 13.5lbs all-in), and there are folks here with both heavier and lighter, longer and shorter FL's.  Just don't go crazy and try to park a monster on it.  If you mean expandable in the software sense, the PMC8 controller is control-program agnostic, and is not tied to any one. 
 
I can see Polaris, so for me a PA is easy (via Sharpcap), but there are folks here who can't see it and have found alternatives.  If they don't step in on this thread, just do a post like "How do I do a PA when I can't see Polaris?", and folks will likely show up with advice.
 
If you intend to do astrophotography, then think about plate solving.  No need for 2/3-star alignments and a blocked horizon no longer matters.  I do a PA and slew to where Cartes du Ciel thinks my target is.  It will be close, but not necessarily in-frame.  Then I tell Astrotortilla (integrated with BackYard Nikon) to center-and-sync.  It requests a picture, plate solves the picture, does a small slew to correct the mount's position, rinse and repeat a couple of times, and after a couple of minutes, my target is centered and my mount sync'd.  It's magic, and this is just my software stack - there are others that can do this as well.   
 
Your 75-80mm tripod footprint is touch-and-go.  Assuming that the tripod legs are collapsed down for AP, that's awfully close to their spacing (which probably varies a bit between mounts).  Basically the tripod legs are hinged and swing up-and-out until they bump into a stop on the tripod head.  Tightening the threaded rod that ties the mount head and eyepiece holder together creates an outward push against the legs, and holds them tight against that stop.  
 
So...for your small EXOS2 tripod footprint, I would think your options are:
#1- Try it and see. It might work...
#2- Come up with a platform extension for the porch.  You shouldn't need much overhang and this would have the advantage that you could put a safety lip on the edge so the legs can't slide off.
#3- Shim the stops on the tripod head, so the legs hit the stops sooner and the footprint is reduced by the little bit that you you need, to fit in the available space.
 
Maybe there are other ideas, but that's what comes to mind so far...  No idea about the Vixen shaft.
 
- Bob
--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Saif
 
Edited

What are the chances of the EXOS2 PMC8 fitting on to one of these pillars. Would be my ideal setup:

Pillar For SkyWatcher EQ5


Sky-Watcher Pillar Mount
That picture should be a little more clearer showing the key on top
Diameter of the tube is 0.12m.
Baader has a page full of adapters but I'm not sure of the EXOS mount head.

 

Saif,
 
What problem are you trying to solve with this? 
 
If it's the 75-80mm porch footprint that you wanted to operate within, this would likely have a *larger* footprint than the standard tripod.  Specs are scarce, but TS-Express says that its beams (legs) are 420mm, and the post is 100mm, so the diameter of the circle the legs enclose would be (420+50)x2=940mm, give or take.  
 
The circle described by the feet of either the tripod or pillar is a worst-case approximation, as fit would really be about the set of triangles that the feet make on your porch, how you have the tripod turned in the space available, and how much clearance you and your payload and weight bar need from their surroundings.  
 
But I think it does help answer whether the pillar (portable pier) would help with your footprint issue or not.  
 
If it was me, magically transplanted into your situation, I'd try the stock tripod (which comes with the mount anyway), on the porch, and if I needed just another inch or two of footprint reduction I'd try shimming the hinge just above the bolt that acts as the hinge pin.  Pic attached of the location.  The mechanical advantage is huge, so something thin and broad (such as a strip of very thin sheet metal) might be all you need to move a foot inward appreciably.  Just keep the legs even, so that they all splay out to about the same distance (because reasons).  
 
The footprint scenario you described might be ok out-of-the-box, but it's really too close to call.  You'll have the tripod anyway, so give it a go and if it's just too tight, there's probably an inch or two of additional footprint reduction available by shimming the hinges just a small amount.  
 
If that's not enough, you're probably into more creative construction in order to take advantage of the location you want to use, no matter what mount you get.  
 
Hope this helps..



--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Saif
 

Wedging some metal sheet in there does sound like a quick practical and simple way to get a smaller radius on the lower end. Thanks for that idea.
For me, the portable pillar mount is just less obtrusive below the ota. It allows easy cable management straight down the pillar and along floor. Cons are probably some degradation in vibration damping for the system and trip hazzard over the feet, but you tend to develop a 6th sense for their whereabouts after a while. I'm probably a little biased, beng the owner of an LX3 Meade MTS decades ago. I just think they are the bees knees aesthetically too.
the raduis for an EQ5 portable pillar is apparently just a little over 80cm but the overall base could be used flat.
I wonder if the bottom of the EXOS2 has that Pin hole underside and a lip that would hang over that 0.12m pillar diameter. I may have posted the EQ6 version of the pillar by the way? This is a schematic:


I might also be mentioning this as a nudge to the EXOS mod people for a new product line 😉

Regards,
Saif


From: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io> on behalf of Robert Hoskin <devonshire@...>
Sent: 07 January 2020 16:07
To: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io>
Subject: Re: [ESPMC-Eight] EXOS2 PMC-Eight #EXOS2
 
Saif,
 
What problem are you trying to solve with this? 
 
If it's the 75-80mm porch footprint that you wanted to operate within, this would likely have a *larger* footprint than the standard tripod.  Specs are scarce, but TS-Express says that its beams (legs) are 420mm, and the post is 100mm, so the diameter of the circle the legs enclose would be (420+50)x2=940mm, give or take.  
 
The circle described by the feet of either the tripod or pillar is a worst-case approximation, as fit would really be about the set of triangles that the feet make on your porch, how you have the tripod turned in the space available, and how much clearance you and your payload and weight bar need from their surroundings.  
 
But I think it does help answer whether the pillar (portable pier) would help with your footprint issue or not.  
 
If it was me, magically transplanted into your situation, I'd try the stock tripod (which comes with the mount anyway), on the porch, and if I needed just another inch or two of footprint reduction I'd try shimming the hinge just above the bolt that acts as the hinge pin.  Pic attached of the location.  The mechanical advantage is huge, so something thin and broad (such as a strip of very thin sheet metal) might be all you need to move a foot inward appreciably.  Just keep the legs even, so that they all splay out to about the same distance (because reasons).  
 
The footprint scenario you described might be ok out-of-the-box, but it's really too close to call.  You'll have the tripod anyway, so give it a go and if it's just too tight, there's probably an inch or two of additional footprint reduction available by shimming the hinges just a small amount.  
 
If that's not enough, you're probably into more creative construction in order to take advantage of the location you want to use, no matter what mount you get.  
 
Hope this helps..



--
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64