Mesu mount (all versions) owner's thread

[astronomer2002]

HELP!!!

I wonder if there are any MESU 200 owners out there who still use Argo Navis and ServoCat.

 

I have just done something very stupid. I decided to update my firmware to the latest version from 2.04. I had a lot of difficulty getting the Argonaut updating software to work with the serial interface to download the setup info, so I just tried uploading the new firmware to see if that made any difference. It did, it worked. Even trying to stop it in a few seconds was not fast enough.

Unfortunately the firmware on the ArgoNavis is now fried so I have no option but to load a new version.

What I am after is the setup info from a working Argo Navis system - maybe the backup from a firmware update you did a while back? I've tried Lucas, but no reply as yet.

 

Thankyou for any help

 

Regards

 

Ian B

[old_eyes]

Another question for all you Mesu/SiTech gurus out there.

I have a Mesu e200 managed by the SiTech Controller using the 0.95GWin version of SiTech.exe.

I run this from Voyager normally, but I have also used NINA successfully.

After a little bit of initial trouble getting Voyager to manage the meridian flips properly, I got everything sorted out, and it has performed faultlessly for the last year.

Now I have found a situation where it does not work as expected.

Most of my imaging is done to the South and West, as these are my darkest skies. I have a town to my East and a city to my North, both of which produce a significant skyglow, particularly at low altitudes. So up to now I have never really done much imaging directly to the North and certainly not at lower altitudes.

A couple of weeks ago, I was imaging fairly near the pole, saw that a meridian flip under the pole would occur during the run, and decided that although it was lower than I would usually image, I would risk it. The target crossed the meridian below the pole, but the flip never happened. The mount carried on to the Track Past Meridian limit and stopped. I abandoned that run and switched to another target.

Doing some daytime testing, I discovered something odd.

Under normal conditions, the Voyager window monitoring the mount counts time down to zero from a negative value as the target approaches the meridian. Reaches zero at the meridian and then starts to count time up after the meridian crossing. Once the Voyager wait time for the meridian flip is exceeded and the current exposure has finished, the mount executes a smooth flip and everything carries on. This happens at any altitude through the zenith and down to the pole.

However, if the target is below the pole, the mount shows an offset from -12 hrs to meridian crossing, and as it crosses the meridian it starts to count down from 12 hrs to flip.

These are my Voyager and SiTech.exe parameters:

The same weird -12hrs to +12hrs switch occurs with NINA, and neither Voyager nor NINA execute a meridian flip. 

In the SiTech.exe SkyView the over the meridian limit is clearly shown in the correct place for both over pole and under pole.

Does anyone recognise this problem? Is it to do with my SiTech settings? 

It is not a huge issue as this is a terrible part of the sky for me to image, but I would like to understand.

Note: I have not tested what happens with a circumpolar target that crosses the meridian twice as that would take a lot of time. My daylight testing involved picking a target that was just before the under pole meridian.

 

[Eyes Wide]

I live in Canada and have the original Mesu mount that I no longer use. Is anyone interested?

[whipdry]

18 hours ago, old_eyes said:

Another question for all you Mesu/SiTech gurus out there.

I have a Mesu e200 managed by the SiTech Controller using the 0.95GWin version of SiTech.exe.

I run this from Voyager normally, but I have also used NINA successfully.

After a little bit of initial trouble getting Voyager to manage the meridian flips properly, I got everything sorted out, and it has performed faultlessly for the last year.

Now I have found a situation where it does not work as expected.

Most of my imaging is done to the South and West, as these are my darkest skies. I have a town to my East and a city to my North, both of which produce a significant skyglow, particularly at low altitudes. So up to now I have never really done much imaging directly to the North and certainly not at lower altitudes.

A couple of weeks ago, I was imaging fairly near the pole, saw that a meridian flip under the pole would occur during the run, and decided that although it was lower than I would usually image, I would risk it. The target crossed the meridian below the pole, but the flip never happened. The mount carried on to the Track Past Meridian limit and stopped. I abandoned that run and switched to another target.

Doing some daytime testing, I discovered something odd.

Under normal conditions, the Voyager window monitoring the mount counts time down to zero from a negative value as the target approaches the meridian. Reaches zero at the meridian and then starts to count time up after the meridian crossing. Once the Voyager wait time for the meridian flip is exceeded and the current exposure has finished, the mount executes a smooth flip and everything carries on. This happens at any altitude through the zenith and down to the pole.

However, if the target is below the pole, the mount shows an offset from -12 hrs to meridian crossing, and as it crosses the meridian it starts to count down from 12 hrs to flip.

These are my Voyager and SiTech.exe parameters:

The same weird -12hrs to +12hrs switch occurs with NINA, and neither Voyager nor NINA execute a meridian flip. 

In the SiTech.exe SkyView the over the meridian limit is clearly shown in the correct place for both over pole and under pole.

Does anyone recognise this problem? Is it to do with my SiTech settings? 

It is not a huge issue as this is a terrible part of the sky for me to image, but I would like to understand.

Note: I have not tested what happens with a circumpolar target that crosses the meridian twice as that would take a lot of time. My daylight testing involved picking a target that was just before the under pole meridian.

 

Hello, 

I don't use Voyager... having briefly looked at the mount section of the help files you might try some of the other setting as mentioned in the screen shot text below. 

Peter

[tomato]

Just a quick question  on what version of Sitech.exe folks are running. The website has version P available but I’ve just been given a link to version X via the forum to fix an ASCOM clock disparity issue flagged up by the latest version of NINA. However, this version isn’t on the official website as far as I can see?

[whipdry]

2 hours ago, tomato said:

Just a quick question  on what version of Sitech.exe folks are running. The website has version P available but I’ve just been given a link to version X via the forum to fix an ASCOM clock disparity issue flagged up by the latest version of NINA. However, this version isn’t on the official website as far as I can see?

Complete list in the attached text file from here; https://groups.io/g/Sitechservo/files/AAAA SiTech URLs - Latest Current software

Just copy & paste into your browser whichever version from the text file you require & it should download... I've used X on both mk1 & mk2 Mesu mounts. 

Peter

 

SiTech URLs Feb2022.txt

Edited May 18, 2022 by whipdry

[Laurin Dave]

http://siderealtechnology.com/SiTechSetup095X.exe

Here it is Steve, not that I'm using it.. It was reported in the Sitechservo user group by a NINA user, Dan Gray fixed it with this update ... apparently it had been that way since day one! (ie Sitech reporting time as local rather than UTC)

[Jonk]

The website is not very well maintained, and the versions shared on the groups.io pages are considered beta. I believe the latest version is X as mentioned.

Don’t forget you can test sitech.exe in simulation to make sure everything works before replacing the version on the computer running your kit.

[tomato]

Thanks all for the replies. Before I saw them, I tried to download the latest file from the forum, but you’ve guessed it Win 10 wouldn’t have it, too much of a security risk..

So I used some dodgy shareware to transfer it from an iPad download, how does that make sense Microsoft?

In the midst of the head scratching last night I managed to initiate a go to with the RA lock on😳 but after this it was guiding at 0.35”.

What a mount…

[Jonk]

On 18/05/2022 at 13:28, tomato said:

Before I saw them, I tried to download the latest file from the forum, but you’ve guessed it Win 10 wouldn’t have it, too much of a security risk..

 

Yes that also happened on FF for some versions, it’s down to how they put the file on their webserver for general download. Sometimes it’s not done correctly.

In FF you just accept the risk and it downloads.

Also, it’s worth mentioning, sometimes just the .exe file is made available, other times it’s the entire install package.

It can be confusing, so use the groups.io forum as much as possible to keep up.

There’s also a mesu specific one but it’s not as active.

People only tend to question when things aren’t working correctly - surely that tells you a lot about the mount design.

[ollypenrice]

On 22/04/2022 at 12:54, astronomer2002 said:

Looking at updating my Mesu200 from Servocat to Sitech. There seems to be a huge price difference between Sitech I and Sitech II - has anyone got a Mesu 200 with Sitech I?

I will be grateful for any help/advice

 

Ian B

 

Oh how I love the Servocat-Argonavis version. In the last ten years I don't think I have ever read a post asking why this or that didn't work! I have no intention of upgrading my difficultioes!

😁lly

[ollypenrice]

On 22/04/2022 at 12:54, astronomer2002 said:

Looking at updating my Mesu200 from Servocat to Sitech. There seems to be a huge price difference between Sitech I and Sitech II - has anyone got a Mesu 200 with Sitech I?

I will be grateful for any help/advice

 

Ian B

 

Oh how I love the Servocat-Argonavis version. In the last ten years I don't think I have ever read a post asking why this or that didn't work. I have no intention of upgrading my difficulties!

😁lly

[tomato]

It’s definitely worth contacting Lucas as the Mk 2 Mesu doesn’t have the same encoders as the Mk 1 and uses the Sitech 1 unit. It might be possible to ‘dumb down’ your Mesu to run with the Sitech 1. I have seen a used Mesu 200 for sale with one encoder disconnected from the Sitech 2, presumably because the encoder had stopped working. 
 

With modern quick and reliable plate solving, absolute encoders are not essential.

[dan_adi]

1 hour ago, tomato said:

It’s definitely worth contacting Lucas as the Mk 2 Mesu doesn’t have the same encoders as the Mk 1 and uses the Sitech 1 unit. It might be possible to ‘dumb down’ your Mesu to run with the Sitech 1. I have seen a used Mesu 200 for sale with one encoder disconnected from the Sitech 2, presumably because the encoder had stopped working. 
 

With modern quick and reliable plate solving, absolute encoders are not essential.

Neither Mesu Mk1 or Mk2 use absolute encoders. The Mesu 300 is fitted with Renishaw absolute encoders on RA and DEC, most likely the common 26 bit ones (that is 2^26, or ~67 million tiks per rev, or 51.78 ticks/arcsec that gives a resolution of 0.019 arcseconds per tick)

Indeed absolute encoders (Renishaw) are not essential, but they do improve tracking and pointing substantially  on any mount design, and most importantly give you more time to focus on imaging. Pair that with a good pointing/tracking model software like PointXP (in case of sitech or planewave) and autoguiding is no longer needed for subs ranging from 5 to 20 min or so. Expose longer than that and you will have to guide, but the guiding will be very gentle (low aggression and rare, like 10 sec exposures once or twice a minute). But with new, sensitive CMOS  camera who exposes for 20-30 min per sub these days anyway .. 

When I get my Mesu 200 fitted with Renishaw 26 bit encoders I will give a more hands-on experience, besides the usual theory, but I have to say I haven't seen anyone complain about using absolute encoders ... 

This is a great presentation by Dan Gray from Sitech about improving mounts: 

 

 

Edited May 23, 2022 by dan_adi

[Neil27]

On 18/05/2022 at 13:28, tomato said:

Thanks all for the replies. Before I saw them, I tried to download the latest file from the forum, but you’ve guessed it Win 10 wouldn’t have it, too much of a security risk..

So I used some dodgy shareware to transfer it from an iPad download, how does that make sense Microsoft?

In the midst of the head scratching last night I managed to initiate a go to with the RA lock on😳 but after this it was guiding at 0.35”.

What a mount…

I had that the other night after upgrading my observatory PC from an ageing 9 year old Lenova to a spanking brand new Beelink. The software download gave me loads of warning, just clicking through them allowed the download to continue and finally, SiTech exe and SiTech config files appeared on my desktop and in the windows folders.

The joy of now getting my new PC talking to the mount now awaits …. Again 😊

Glad you got it sorted though @tomato, although it does seem a convoluted way of getting the download to work!

[Neil27]

16 hours ago, ollypenrice said:

Oh how I love the Servocat-Argonavis version. In the last ten years I don't think I have ever read a post asking why this or that didn't work. I have no intention of upgrading my difficulties!

😁lly

You obviously Love it so much Olly one has to let the world know twice …. 🤪😉

I envy the simple set up, but alas I can’t see how my Mesu would work otherwise without a PC in the mix?

I like the idea of tablet control, like the ZWO Asair set up but for the life of me neither have the technical skill or faintest idea of how that would work!

Also I would like to hold my hands up and declare the only issue I have ever had with the mount was entirely my own ineptitude and lack of knowledge. When set up and running, these mounts are fire up and forget! Touch wood 🙃😉

[old_eyes]

On 07/05/2022 at 08:34, whipdry said:

Hello, 

I don't use Voyager... having briefly looked at the mount section of the help files you might try some of the other setting as mentioned in the screen shot text below. 

Peter

Thanks for the suggestion. I have tried the different ASCOM pier mode options, but they do not cure the problem. It is very much an edge issue as I almost never image under the circumstances that trigger the problem, so I think I will just live with it! If I do want to image that part of the sky, I will just have to make sure I am around when a meridian flip is called for. Alternatively I can force a merdian flip in SiTech and trust the software to reacquire the target. If I set the SiTech flip to occur after the ASCOM initiated flip should have happened, it will only kick in when the Voyager or NINA triggered flip fails.

[ollypenrice]

41 minutes ago, Neil27 said:

You obviously Love it so much Olly one has to let the world know twice …. 🤪😉

I envy the simple set up, but alas I can’t see how my Mesu would work otherwise without a PC in the mix?

I like the idea of tablet control, like the ZWO Asair set up but for the life of me neither have the technical skill or faintest idea of how that would work!

Also I would like to hold my hands up and declare the only issue I have ever had with the mount was entirely my own ineptitude and lack of knowledge. When set up and running, these mounts are fire up and forget! Touch wood 🙃😉

Sorry to repeat myself! The joy of the real Mk1 is that it is PC free and standalone. I remain a great fan of the handset mount, having had so many fights with externally controlled ones.

Olly

[astronomer2002]

On 23/05/2022 at 17:53, ollypenrice said:

Oh how I love the Servocat-Argonavis version. In the last ten years I don't think I have ever read a post asking why this or that didn't work. I have no intention of upgrading my difficulties!

😁lly

I have had to replace the rotary selector switch on the AN and one of the buttons on the Servocat hand controller. These were both iffy and making it impossible to iron out exactly what was happening. This has somewhat delayed my getting to use the mount. Now those are sorted I am trying to get to grips with actually using the mount.

I am struggling to get my Mesu 200 Servocat/ArgoNavis system to perform as well as I expect it to.

This is probably down to incorrect settings in both ArgoNavis, which I accidentally lost during a software upgrade, and the Servocat, which had not been set up correctly by a previous owner.

What I would like to know is the settings for the Servocat. I have asked Lucas, but he doesn't seem to have a record of the original settings. He did advise me the gear ratio should be around 2000 for the original Mesu (mine was set to 6000

Can anyone post a screenshot of their working Servocat system setup? (Olly maybe?)

I have set the mount up temporarily on a tripod and using a C5 to try to iron out the issues. I have a rough polar alignment  so not expecting pinpoint goto's, but they are close.

Something odd is happening though. When I do a goto the mount slews to roughly the right place and beeps when it thinks it is there. However, on the AN screen there is a residual amount in both RA and Dec. If I press goto on the Servocat handbox again, the mount moves closer to the desired point. Sometimes at this point the object is in the field of view and sometimes a third press of 'goto' is needed.

So it almost works, but not quite.

Tracking appears to be fine.

Another oddity is what happens if I connect a PC with Stellarium to the AN. Issuing goto's from Stellarium seems to work fine, but I am left with odd behaviour as the mount tracks. As the planetarium program relies on AN to tell it where the mount is pointing I see the telescope position on the program display drifting for a few seconds and then it jumps back to the centre of the correct object. It has been suggested this behavior is down to the resolution of the shaft encoders attached to the AN, which have 10,000 steps per revolution, meaning 1 step is 2.16 minutes of arc. The Servocat is tracking so the object doesn't move in the field, but on the planetarium program and the AN screen it looks like tracking has stopped until the next 'click' is recorded by the shaft encoders.

Hopefully the above is clear to AN/Servocat Mesu users, and you recognise this behaviour as 'normal'.

I really do need some help with the goto issue though as this is spoiling the usability of this mount.

I will be grateful for any help. This is a good mount but rather complicated to set up.

 

Ian b

[ollypenrice]

18 hours ago, astronomer2002 said:

I have had to replace the rotary selector switch on the AN and one of the buttons on the Servocat hand controller. These were both iffy and making it impossible to iron out exactly what was happening. This has somewhat delayed my getting to use the mount. Now those are sorted I am trying to get to grips with actually using the mount.

I am struggling to get my Mesu 200 Servocat/ArgoNavis system to perform as well as I expect it to.

This is probably down to incorrect settings in both ArgoNavis, which I accidentally lost during a software upgrade, and the Servocat, which had not been set up correctly by a previous owner.

What I would like to know is the settings for the Servocat. I have asked Lucas, but he doesn't seem to have a record of the original settings. He did advise me the gear ratio should be around 2000 for the original Mesu (mine was set to 6000

Can anyone post a screenshot of their working Servocat system setup? (Olly maybe?)

I have set the mount up temporarily on a tripod and using a C5 to try to iron out the issues. I have a rough polar alignment  so not expecting pinpoint goto's, but they are close.

Something odd is happening though. When I do a goto the mount slews to roughly the right place and beeps when it thinks it is there. However, on the AN screen there is a residual amount in both RA and Dec. If I press goto on the Servocat handbox again, the mount moves closer to the desired point. Sometimes at this point the object is in the field of view and sometimes a third press of 'goto' is needed.

So it almost works, but not quite.

Tracking appears to be fine.

Another oddity is what happens if I connect a PC with Stellarium to the AN. Issuing goto's from Stellarium seems to work fine, but I am left with odd behaviour as the mount tracks. As the planetarium program relies on AN to tell it where the mount is pointing I see the telescope position on the program display drifting for a few seconds and then it jumps back to the centre of the correct object. It has been suggested this behavior is down to the resolution of the shaft encoders attached to the AN, which have 10,000 steps per revolution, meaning 1 step is 2.16 minutes of arc. The Servocat is tracking so the object doesn't move in the field, but on the planetarium program and the AN screen it looks like tracking has stopped until the next 'click' is recorded by the shaft encoders.

Hopefully the above is clear to AN/Servocat Mesu users, and you recognise this behaviour as 'normal'.

I really do need some help with the goto issue though as this is spoiling the usability of this mount.

I will be grateful for any help. This is a good mount but rather complicated to set up.

 

Ian b

I don't know how to give you a screenshot of the Argonavis settings but I can have a look through the parameters I've put into it. I won't be able to get to this straight away because I'm in mid project and we have guests but I'll see what I can do.

The encoders are not very accurate. They are fine for finding a target but you cant note the RA and Dec positions, feed them in on another night and expect them to re-frame perfectly. My mount's first owner tried to get it to run from a planetarium but couldn't make it work. Since he's an IT professional and I'm an IT turnip farmer, I have never tried again.

You'll get there.

Olly

[astronomer2002]

5 hours ago, ollypenrice said:

I don't know how to give you a screenshot of the Argonavis settings but I can have a look through the parameters I've put into it. I won't be able to get to this straight away because I'm in mid project and we have guests but I'll see what I can do.

The encoders are not very accurate. They are fine for finding a target but you cant note the RA and Dec positions, feed them in on another night and expect them to re-frame perfectly. My mount's first owner tried to get it to run from a planetarium but couldn't make it work. Since he's an IT professional and I'm an IT turnip farmer, I have never tried again.

You'll get there.

Olly

Olly,

 

Thankyou for your offer, I was beginning to think there's no-one else out there running the Servocat/ArgoNavis control mechanism on a Mesu mount. What I need as well is the Servocat parameters which you can get from the Servocat setup program.

I had no difficulty getting Stellarium to talk to the ArgoNavis, after making up the correct serial cable and setting the com values the same at both ends. It is the only one I have tried, but I can say it does work.

 

Here's a page from the Servocat manual below:-

The encoder resolution is from the motors used, and seems to always be 2000. The gear ratio I got from Lucas, and he thought it was 2000 for the original Mesu.

I have no idea what the other values should be for the Mesu but the mount slews at a reasonable rate so is probably about right. The jog rate on mine seems slow. I don't know what to set for the accelerate/decelerate rate and wonder if my issue lies there.

The goto's would work fine if they actually ended up where the ArgoNavis told the mount to move to. Press the goto button once and the mount gets closer than a degree to the object before announcing the move completed successfully.  Unfortunately the mount requires the Servocat controller Goto but to be pressed again to encourage the mount to move closer (which it does).

 

 

[ollypenrice]

@ Ian B

How do I see what the Servocat settings are? Do I connect it to a PC somehow? I've never done this. Or is the information on the AN controller display?

Olly

Edited June 23, 2022 by ollypenrice

[dan_adi]

Small update:

If you use Prism v.10 with a Mesu mount, in the Misc tab, Nutate coords and Aberration coords should be unchecked, to avoid correcting twice. Don't know about other software, but the sitech manual states the for TheSkyx these options should also be unchecked. So better to ask SGP, NINA, Stellarium developers how their software report the coordinates, because this will affect pointing.

Since I had the mount I've been running with those options checked. Talk about live and learn 😁

Clear skies

Edited June 23, 2022 by dan_adi

[astronomer2002]

On 23/06/2022 at 08:35, ollypenrice said:

@ Ian B

How do I see what the Servocat settings are? Do I connect it to a PC somehow? I've never done this. Or is the information on the AN controller display?

Olly

Olly,

I connected the Servocat to my PC via a standard USB cable (the Servocat has a USB port on the front)

If you had a copy of the original dat file that Lucas should have included with the mount that would be a good starting point for me.

Here's a screenshot of what I have set up

 

[dan_adi]

18 hours ago, astronomer2002 said:

Olly,

I connected the Servocat to my PC via a standard USB cable (the Servocat has a USB port on the front)

If you had a copy of the original dat file that Lucas should have included with the mount that would be a good starting point for me.

Here's a screenshot of what I have set up

 

Have you tried asking mr. Mesu if he has your dat file?