Date   

Re: Unexpected mount movement

Bill Long
 

It was not likely the mount. Lets assume for a second it is not the mount, what would be next on the list?

Drawtube moving would move the star on the frame as well. Have you looked at that? If so how? Do you have a laser you can put in the drawtube and flex the drawtube to see how much play is in it?


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Alex <groups@...>
Sent: Friday, October 15, 2021 8:07 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Unexpected mount movement
 
Not a guiding issue as I'm not guiding.  Since the absolute encoders didn't log they detected any slew or directed movement, then Ray's theory of slippage of the clutch makes sense.  I'm not sure how the slipping happen.  I feel no slippage when I manually try and move the scope.  The clutch knobs were tightened using a hex key.  Maybe there was some movement elsewhere in the imaging train, but everything seems buttoned down.  I imaged all night last night with no problems, so unless it crops up again, I'm assuming it's just one of those mysteries.

Alex


Re: Unexpected mount movement

Alex
 

Not a guiding issue as I'm not guiding.  Since the absolute encoders didn't log they detected any slew or directed movement, then Ray's theory of slippage of the clutch makes sense.  I'm not sure how the slipping happen.  I feel no slippage when I manually try and move the scope.  The clutch knobs were tightened using a hex key.  Maybe there was some movement elsewhere in the imaging train, but everything seems buttoned down.  I imaged all night last night with no problems, so unless it crops up again, I'm assuming it's just one of those mysteries.

Alex


WoW! Another APOD for Ignacio

Roland Christen
 

https://apod.nasa.gov/apod/ap211014.html

With his 168mm refractor that I made from some one-off glass I had on hand. Maybe I should make some more of them?

Anyway, congratulations Ignacio. You are making good use of that scope.

Rolando

--
Roland Christen
Astro-Physics


Re: Setting up NINA

ap@CaptivePhotons.com
 

Bruce Donzanti wrote:

 

  • I set up in NINA for the first time yesterday. I was asked to have NINA sync with the mount or vice vera. I synced NINA to the mount/telescope (AP1100 in park 4). It slewed fine during the day. Now trying it at night and after I unpark it, it slews but to the wrong location. I looked at a DSO (e.g., Bubble N) in the Sky Atlas. It came up but the coordinates and transit are wrong and, of course, it slewed to the wrong area of the sky. I am in a permanent setup and my location coordinates are correct. I tested using SkySafari and the scope slewed to the correct location. Any suggestions as to what am I doing wrong would be appreciated.

 

 

NINA uses the computer clock, so assuming it is approximately right, if its sky atlas is wrong, it is likely the lat/long.   Perhaps a missing minus sign?  USA is + for lat, - for long (sorry if that's obvious).

 

Other things you can check:

 

Date and time the same in the mount (normally APCC Advanced Settings, Keep Mount time synced to PC time will do it). 

 

Check the lat/long and see if they are right in all places -- I am still not completely sure how the sites in APCC and ASCOM differ but they should end up being the same).

 

Under NINA, Options, Equipment, Telescope there is a "Do not sync" which should be turned off.

 

ASCOM Driver Additional Conf settings check the Use RECAL for Sync's (should be on).

 

After you unpark at night, I would slew somewhere and plate solve so it can do a sync. You can do it in APPM (whether there is a model in use or not) under the Plate Solve and Recal, or do it in NINA with a slew and center command either in a sequence or from framing assistant.  This should get APCC and NINA in sync (though they really should not have been far off to begin with).  But this is usually for very very minor discrepancies, you seem like you have a major one.

 

Linwood

 


Setting up NINA

Bruce Donzanti
 

I set up in NINA for the first time yesterday. I was asked to have NINA sync with the mount or vice vera. I synced NINA to the mount/telescope (AP1100 in park 4). It slewed fine during the day. Now trying it at night and after I unpark it, it slews but to the wrong location. I looked at a DSO (e.g., Bubble N) in the Sky Atlas. It came up but the coordinates and transit are wrong and, of course, it slewed to the wrong area of the sky. I am in a permanent setup and my location coordinates are correct. I tested using SkySafari and the scope slewed to the correct location. Any suggestions as to what am I doing wrong would be appreciated.


Re: Testing SkyTrack continuous tracking with the Mach2 #Mach2GTO

Brent Boshart
 
Edited

Hi Brian,
I am working on documentation for the new release. There is an older video on my website that should help.  First clear night, I will also make a quick start video.
The most common trouble that users have is not setting up the site information correctly. 


Re: Testing SkyTrack continuous tracking with the Mach2 #Mach2GTO

Brent Boshart
 

I always check my executables before uploading with VirusTotal.  There were no detections against all 67 anti-virus vendors.   https://www.virustotal.com/gui/file/0a36ba4d0811ca1c34e0757dcb82ea89cb646c1b998b971b5a9ecfbb8d5dd94d

False positives are quite frustrating as I usually have to contact a few anti-virus vendors to get them to whitelist my software to prevent the false positives.  Thanks for that note Bryan.


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Peter Nagy
 

No hurry and thanks for excellent explanation. 

Peter


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Roland Christen
 

Yes, it's quite smooth. I don't have any pix at my disposal at the moment, but will dig some up when I get back.

Rolando

-----Original Message-----
From: Peter Nagy <topboxman@...>
To: main@ap-gto.groups.io
Sent: Fri, Oct 15, 2021 5:53 pm
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

OK. Without encoders and using spur gears, I assume PE would look somewhat sinusoidal. 

Peter

--
Roland Christen
Astro-Physics


Re: Testing SkyTrack continuous tracking with the Mach2 #Mach2GTO

Worsel
 

FYI

If you have Norton/Symantec as your virus checker on downloaded files, it will quarantine SkyTrack and flag it as WS.Reputation1.  This is NOT an actual virus.  This is Norton's designation for a file that it cannot find in its database, because of low usage statistics.  Not surprisingly, ST 1.5. is quite new; hence low usage.  Not an real problem, but you will have to restore it from quarantine to install.

Thanks to Brent for his effort on ST!!

Bryan


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Peter Nagy
 

OK. Without encoders and using spur gears, I assume PE would look somewhat sinusoidal. 

Peter


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Roland Christen
 

Yes. With encoders it looks the same as the Mach2 with encoders.
Without encoders you have PE but without belt ripple.
Without encoders but with PEM activated, you have low PE and no belt ripple.

Roland

-----Original Message-----
From: Peter Nagy <topboxman@...>
To: main@ap-gto.groups.io
Sent: Fri, Oct 15, 2021 5:32 pm
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

Do you have a similar graph using spur gears instead of belts like from A-P1100GTO mount?

Peter

--
Roland Christen
Astro-Physics


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Peter Nagy
 

Do you have a similar graph using spur gears instead of belts like from A-P1100GTO mount?

Peter


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Roland Christen
 

Actually the graph below shows belt ripple + stepper motor ripple + periodic error. The stepper motor ripple is very small but shows up as tiny wiggles on the belt ripple. The periodic error is the slow downward creep of the tracking graph before the encoders are turned back on. The Mach2 never operates with encoders off, so all these variations in tracking speed are eliminated.

Roland

-----Original Message-----
From: Roland Christen via groups.io <chris1011@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Fri, Oct 15, 2021 5:11 pm
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

I'll answer both your questions.

1) .02 seconds at 1x sidereal is .02 x 15 arc sec per second = 0.3 arc seconds

2) if you didn't know at this point, I would like to make clear that the Mach2 is a completely different animal from any import mount.

The Mach2 has inherent high precision Renishaw Absolute encoders on the output shaft. The tracking rate of the RA shaft is exactly sidereal and the encoders make sure of that by measuring the shaft position hundreds of times per second and correct the driving rate down to a very smooth level. The belt ripple and all other distortions of the sidereal driving rate are gone to within the resolution of the encoder, which is 0.15 arc seconds. That's the accuracy of the output shaft. Without the Renishaw encoder, the Mach2 would be just an ordinary mount like all the other imports.

Below is the tracking of the RA shaft, the one which is basically pointing the telescope and following the stars. It has a very precise motion because it uses encoder feedback like all modern high performance precision machinery. The encoder we use from Renishaw is the best you can buy, bar none. There are no other encoders on the market that can top the accuracy of the Renishaw Resolute encoders, or even come close (there are less expensive Renishaws that don't have this accuracy). This allows the Mach2 to achieve the tracking accuracy needed for real precision imaging. Why did we choose this particular expensive encoder? Because i didn't want to mess around and introduce other errors into the system.

It's all explained on our website if you want to dig further.

Rolando




-----Original Message-----
From: Peter Nagy <topboxman@...>
To: main@ap-gto.groups.io
Sent: Fri, Oct 15, 2021 4:28 pm
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

Inputting MnMo in PHD2 is in pixels. Which is why I like to think in arc-secs and convert to pixels based on my image scale of my equipment. 

How does 0.02 seconds translate Min Move to 0.3 arc-secs? 

Doesn't Mach2 mount have belt drives in place of spur gears in gearboxes? Are you referring import mounts using belts in place of worm gears?

Peter

--
Roland Christen
Astro-Physics

--
Roland Christen
Astro-Physics


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Peter Nagy
 

I didn't realized you were comparing encoded mounts to non-encoded mounts whether gear reduction uses spur gears or pulley belts.

Yes, absolute encoder mounts beat everything else especially when Renishaw encoders are used.

Peter


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Roland Christen
 

I'll answer both your questions.

1) .02 seconds at 1x sidereal is .02 x 15 arc sec per second = 0.3 arc seconds

2) if you didn't know at this point, I would like to make clear that the Mach2 is a completely different animal from any import mount.

The Mach2 has inherent high precision Renishaw Absolute encoders on the output shaft. The tracking rate of the RA shaft is exactly sidereal and the encoders make sure of that by measuring the shaft position hundreds of times per second and correct the driving rate down to a very smooth level. The belt ripple and all other distortions of the sidereal driving rate are gone to within the resolution of the encoder, which is 0.15 arc seconds. That's the accuracy of the output shaft. Without the Renishaw encoder, the Mach2 would be just an ordinary mount like all the other imports.

Below is the tracking of the RA shaft, the one which is basically pointing the telescope and following the stars. It has a very precise motion because it uses encoder feedback like all modern high performance precision machinery. The encoder we use from Renishaw is the best you can buy, bar none. There are no other encoders on the market that can top the accuracy of the Renishaw Resolute encoders, or even come close (there are less expensive Renishaws that don't have this accuracy). This allows the Mach2 to achieve the tracking accuracy needed for real precision imaging. Why did we choose this particular expensive encoder? Because i didn't want to mess around and introduce other errors into the system.

It's all explained on our website if you want to dig further.

Rolando




-----Original Message-----
From: Peter Nagy <topboxman@...>
To: main@ap-gto.groups.io
Sent: Fri, Oct 15, 2021 4:28 pm
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

Inputting MnMo in PHD2 is in pixels. Which is why I like to think in arc-secs and convert to pixels based on my image scale of my equipment. 

How does 0.02 seconds translate Min Move to 0.3 arc-secs? 

Doesn't Mach2 mount have belt drives in place of spur gears in gearboxes? Are you referring import mounts using belts in place of worm gears?

Peter

--
Roland Christen
Astro-Physics


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

jimwc@...
 

On Fri, Oct 15, 2021 at 02:14 PM, Roland Christen wrote:
Roland
You inferred that 150mm focal length 50mm diameter guide scope as being inadequate for the Job.
can you give a rule of thumb as to the size guide scope should be and compared to what. so we are talking apples to apples here.
Thanks
Jim


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Peter Nagy
 

My bottom line is I pay more attention to FWHM of stars in images than graphs from auto guider software. Sometimes I get fairly high RMS and still get low FWHM of stars in images. The graphs or numbers from PHD2 are best guesses and not necessarily describing the performance of mounts. 

Peter


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Roland Christen
 

Unfortunately rms is not a good representative of tracking because it basically smooths out peak excursions that can leave stars eggy or having small appendages. I would rather have consistent 1 arc sec P-P than 0.2 arc sec rms with occasional 5 arc sec peaks. I do like the bullseye that shows where the guide star is for each exposure. Patterns in the bullseye that look like globular clusters indicate good tracking. When they look like open clusters and are oval shaped, that's not good.

Rolando

-----Original Message-----
From: steve.winston@...
To: main@ap-gto.groups.io
Sent: Fri, Oct 15, 2021 4:17 pm
Subject: Re: [ap-gto] RA Mesh adjustment for 2104 model Mach 1 GTO

[Edited Message Follows]
MinMo in PHD2 is set in pixels (or fraction of a pixel), so will vary depending on your guiding image scale.

And RMS in PHD2 is reported in both arc-seconds and pixels, though sometimes people seem to get them mixed up :-/. 
Obviously best if people report their results in arc/s so it's consistent across different set-ups.

--
Roland Christen
Astro-Physics


Re: RA Mesh adjustment for 2104 model Mach 1 GTO

Peter Nagy
 

Inputting MnMo in PHD2 is in pixels. Which is why I like to think in arc-secs and convert to pixels based on my image scale of my equipment. 

How does 0.02 seconds translate Min Move to 0.3 arc-secs? 

Doesn't Mach2 mount have belt drives in place of spur gears in gearboxes? Are you referring import mounts using belts in place of worm gears?

Peter

1961 - 1980 of 84194