Mesu MkII Fails to Flip

[astrophoto_canada]

Hey Everyone

Has anyone with a Mk2 Mesu had issues with it failing to flip? I'm waiting for Lucas Mesu to get back to me but in the meantime thought I'd reach out on here. I've asked a similar question on the Sitech forum too.

The issue I'm having is the mount is behaving like a flip-less mount with the RA continuing to rotate in the same direction when I've issued a goto for targets on the other side of the meridian. For example doing an offset init with the scope looking west, and then performing a goto to an object in the east, causes the CW bar to continue rising (i.e. moving counterclockwise) and scope dips to the face the target in the east.

I've checked every parameter and am using the sitech.cfg file sent to me by Lucas and haven't fiddled with the factory servoconfig either. The only thing I've changed is the lat/long for my location. I've checked the motor/encoder operation is correct per the Operations Manual. Tracking and gotos on the same side of the sky work fine. It's a really perplexing problem thats driving me nuts. 

Thanks in advance!

Gary.

 

 

 

 

 

[astrophoto_canada]

Solved! Although I've yet to try it in practice. 

For those that have the ability to image past the meridian, it possible to set up a precise point where the mount will flip. For example, if say theres a portion of the horizon that is obscured, or may be limited by clearance, you can now define this in sitetch.cfg (Tab Mount Parms -  Overpole and Under Pole). In the config file that Lucas had provided, it was set up not to flip (bended knee arrangement). 

This will be handy in my case as I should (?) be able to independently set the meridian limits East, West  and altitude (or horizon file) to precisely control the flip position. 

This information is in the Help on the Mount Parms config tab, but is not in the older Operations Manual. 

Gary. 

 

[mrpizza]

Thanks for explaining your solution.  I am anxiously awaiting a new one here in the states and am trying to get as much info from new users so I am ready for any "problem" I encounter.

Chris

[astrophoto_canada]

28 minutes ago, mrpizza said:

Thanks for explaining your solution.  I am anxiously awaiting a new one here in the states and am trying to get as much info from new users so I am ready for any "problem" I encounter.

Chris

I found it’s quite a steep learning curve with all of the possibilities available through the sitech controller.  I made couple of mistakes which are obvious in hindsight. Nothing major just things that threw a wrench into the works. Hopefully I’ll get to use if the skies clear! Let me know if you want my .cfg file as it might save you some time.

[mrpizza]

Thanks, I'll keep that in mind.  I removed the G11 and have wires hanging everywhere in anticipation of the arrival.  The pier sure looks naked.  I placed my order so It would get here after hurricane season so I can get right to learning how to use it.  It will hold a new Meade LX850 ACF 14".

Chris

 

 

[Laurin Dave]

There’s a guide written by Steve Richards (a moderator on SGL) which will help with all the settings.   if you search for “Mesu 200 Mount Quick guide to installation” you should find it

[kirkster501]

Yep.  When the flip occurs is entirely controlled by the Sitech under-pole, over-pole settings and track past the pole, as you have found.  I also had this issue when I was new to the Sitech and, until you encounter this issue, maybe months after MESU ownership if you have been either west or east of the meridian and never needed to flip, you can think something is wrong with the mount.  Not at all, if these are set incorrectly the mount just stops when it gets to the Meridian - quite rightly otherwise damage could occur.

These settings are very poorly documented in the Sitech manual.  You can also set them for the flip when scope is pointing North since then, you need to do am opposite flip.  I set mine to 175 so as to flip when 5 degrees past the meridean.  You can see these as lines in the Skyview part of the Sitech install. 

With an astronomy program like CdC you can do dummy syncs and slews during daylight to test these settings by syncing on a star, or roughly where the star would be then, in my example, slewing to a new star 6 degrees past the Meridian which should cause a flip.  Once you have flipped and you then want to slew to a star to the East, an opposite flip should occur.

[astrophoto_canada]

On 29/10/2020 at 17:31, mrpizza said:

Thanks, I'll keep that in mind.  I removed the G11 and have wires hanging everywhere in anticipation of the arrival.  The pier sure looks naked.  I placed my order so It would get here after hurricane season so I can get right to learning how to use it.  It will hold a new Meade LX850 ACF 14".

Chris

 

 

Thats how mine looked .... because it is a short pier I ended up sliding my tripod over it and using my CEM while I waited for the four months for the build!  

[astrophoto_canada]

On 30/10/2020 at 04:42, kirkster501 said:

Yep.  When the flip occurs is entirely controlled by the Sitech under-pole, over-pole settings and track past the pole, as you have found.  I also had this issue when I was new to the Sitech and, until you encounter this issue, maybe months after MESU ownership if you have been either west or east of the meridian and never needed to flip, you can think something is wrong with the mount.  Not at all, if these are set incorrectly the mount just stops when it gets to the Meridian - quite rightly otherwise damage could occur.

These settings are very poorly documented in the Sitech manual.  You can also set them for the flip when scope is pointing North since then, you need to do am opposite flip.  I set mine to 175 so as to flip when 5 degrees past the meridian.  You can see these as lines in the Skyview part of the Sitech install. 

With an astronomy program like CdC you can do dummy syncs and slews during daylight to test these settings by syncing on a star, or roughly where the star would be then, in my example, slewing to a new star 6 degrees past the Meridian which should cause a flip.  Once you have flipped and you then want to slew to a star to the East, an opposite flip should occur.

Yes I was testing this in the daylight using CdC and the inbuilt stuff in Sitech.exe. I automate my flips so it would have showed up as an issue quickly.  The way it was set up was dangerous as it would have collided with the wall and opener mechanism possibly. One inherent safety mechanism though is the mount slips easily as soon as a force >10nm is applied. 

Do you have the mount set up for Reverse Guide Mode (DEC and RA) in Mount Parms? When I flipped to the scope looking west, the RA in PHD2 guiding took off. I'd calibrated looking east and it worked well.  Ran out of darkness to solve the issue. 

Thanks!

Gary.

[kirkster501]

Yes I do have that set up.  I will send you my settings when i am at the mount next.

[tooth_dr]

16 hours ago, astrophoto_canada said:

Do you have the mount set up for Reverse Guide Mode (DEC and RA) in Mount Parms? When I flipped to the scope looking west, the RA in PHD2 guiding took off. I'd calibrated looking east and it worked well.  Ran out of darkness to solve the issue. 

Be interested to hear if you get it sorted.  I still get runaway guiding after a flip and have to recalibrate in phd 2

[astrophoto_canada]

Ok guys I sorted it.

I re-calibrated PHD2 looking east after UNCHECKING "Reverse RA Guide Mode when Looking East (RA). " in the Mount Parms tab. The "Reverse Guide Mode when Looking East (Dec)" remains CHECKED. 

Cheers

Gary.