Date   

Re: PemPro Polar Alignment differs East to West

Andrew Jones
 

Hi Ray. It was pretty much the same for both Alt and Az. I ran it a couple of times and some runs it showed up to a 7 arc mins difference in Az, but pretty much stayed in the 3-5 arc min range for Alt.


Re: PemPro Polar Alignment differs East to West

Joe Zeglinski
 

Rolando,
 
    I think I have found the solution to solving the east-west PemPro curve difference. Simple really.
 
    Atmospheric refraction is ALREADY being taken into account by Ray’s PemPro algorithm, so it really should not be an issue here. However, if there is even some slight variation, during the target run, greater in the western part of the sky, one could very easily produce an “Averaged East-West Pier side” curve by the following procedure:
 
    Rather than settling on doing a raw data sample run for say 6 cycles – Either on one side of the pier, or on the flip side - (and ... further, assuming there are no obstructions for a “reasonable”  span on the prime meridian) – lets start pointing toward the eastern sky, by HALF the suggested (or chosen) offset angle, and let PemPro run past the meridian ending at the same offset half-angle on the western sky, to finish its LAST 3 cycles.
 
    Doing PemPro this way, the target has the SAME amount of EVER decreasing & then increasing atmospheric refraction, for the same number of cycles, split between the two sides of the pier.
 
    What might make this easier, would be if PemPro could make a note of the “actual” pre-meridian offset angle – since the user may have caused some angle delay in preparation of the run, such as the required Calibration wizardry,  and run the other HALF of the cycles until the same post-meridian angle is reached. At that point,  PemPro automatically ends itself,  in preparation for the resulting raw data curve  analysis phase.
 
    The option screen may need to be changed from choosing the number of cycles, or duration – to time or angle ahead and after crossing the meridian.
 
    I think this would be ideal.
Joe Z.


Re: PemPro Polar Alignment differs East to West

Roland Christen
 

Hi Joe,

Thanks for your thoughts.

One could try the zenith to see if the drift in Dec is the same on either side.

By the way, I got to thinking about your daytime polar alignment routine and decided to modify it for our new mounts that have the 90 degree engraving marks on the axes. You must have the pier or tripod level for this to work. All you have to do is line up the RA and Dec engraved marks with the scope pointing to Park3 position (Home position) and tighten both sets of clutches. Then send the mount to either Park1 or Park4 and level the telescope tube assembly using the altitude adjuster.
That's it, and now all you need to adjust is the azimuth angle and that can be done by sending the scope to the Sun (with proper filter or use the ring shadow method). Turn the azimuth until the Sun lines up with the scope. You may have to move the RA axis a small amount using the E-W buttons if your keypad time is off, then press Recal. Now you are ready to slew to other bright planets or stars.

Rolando



-----Original Message-----
From: 'Joseph Zeglinski' J.Zeglinski@... [ap-gto] <ap-gto@...>
To: ap-gto
Sent: Sat, Mar 3, 2018 2:32 pm
Subject: Re: [ap-gto] PemPro Polar Alignment differs East to West



Hi Rolando,
 
    I too have seen that PemPro curve results discrepancy on runs east vs. west side of the mount.
I REALLY like your explanation, on the cause – even if the results might sometimes be slight. They could be further exaggerating with poor seeing, besides the atmospheric component adding to the discrepancy.
 
    Yes - if you run PemPro with the “standard” setting of 5 minutes  (deg ?) looking toward the east of PM, the OTA is “rising” and the atmospheric refraction is “actually improving”, all during the hour long RAW data sampling.
 
    On the flip side, running with exactly the same PemPro meridian target offset, the atmospheric refraction  can ONLY  “degrade” steadily for the entire western sky target  run.
 
    So, you have the worst of both situations. You can either trust the optimum raw data when PemPro runs from the west side of the pier on eastern targets, or the twice as bad situation with “STEADILY declining”  target Altitude ... when running with the scope on the east side (looking west).
 
    I brought this up, on this Group probably more than a couple of years ago, suggesting that PemPro could be run twice, and the two raw data curves averaged – or their samples interleaved – to come to some averaged curve result. Requires some further thinking, whether the results “should be weighted” more toward eastern targets, Something for Ray to consider, based on your premise.
 
    Anyway, Rolando, thanks for this explanation of what has been frustrating me about my own PemPro results ... for a VERY long time. Unfortunately, in the short term, we just have to live with this minor discrepancy.
 
Joe



Re: PemPro Polar Alignment differs East to West

Joe Zeglinski
 

Hi Rolando,
 
    I too have seen that PemPro curve results discrepancy on runs east vs. west side of the mount.
I REALLY like your explanation, on the cause – even if the results might sometimes be slight. They could be further exaggerating with poor seeing, besides the atmospheric component adding to the discrepancy.
 
    Yes - if you run PemPro with the “standard” setting of 5 minutes  (deg ?) looking toward the east of PM, the OTA is “rising” and the atmospheric refraction is “actually improving”, all during the hour long RAW data sampling.
 
    On the flip side, running with exactly the same PemPro meridian target offset, the atmospheric refraction  can ONLY  “degrade” steadily for the entire western sky target  run.
 
    So, you have the worst of both situations. You can either trust the optimum raw data when PemPro runs from the west side of the pier on eastern targets, or the twice as bad situation with “STEADILY declining”  target Altitude ... when running with the scope on the east side (looking west).
 
    I brought this up, on this Group probably more than a couple of years ago, suggesting that PemPro could be run twice, and the two raw data curves averaged – or their samples interleaved – to come to some averaged curve result. Requires some further thinking, whether the results “should be weighted” more toward eastern targets, Something for Ray to consider, based on your premise.
 
    Anyway, Rolando, thanks for this explanation of what has been frustrating me about my own PemPro results ... for a VERY long time. Unfortunately, in the short term, we just have to live with this minor discrepancy.
 
Joe


Re: PemPro Polar Alignment differs East to West

Ray Gralak
 

Going from 1 to 3-5 arc-mins is actually not that much. Was the change mostly in azimuth, altitude, or both?

It could be that weight shift from the pier flip is causing some movement.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma

-----Original Message-----
From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Saturday, March 3, 2018 11:08 AM
To: ap-gto@yahoogroups.com
Subject: [ap-gto] PemPro Polar Alignment differs East to West



Hello Everyone. I am looking for some guidance. I have a Mach 1 on a permanent pier in an observatory that I am in
the process of getting setup. I currently have a 11" EdgeHD SCT mounted on the Mach 1. Last night I finally got
around to getting my polar alignment dialed it. I have been using a PoleMaster to get me pretty close, but wanted to
see if I could further refine the alignment using PemPro 3 since I had recently paid for the upgrade.

I started the PEMPro Alignment Wizard on the West side of the Meridian and did both the Azimuth and Altitude
alignments several times until I got both under 1 arc min which was pretty much the limit of my Seeing last night. I then
decided to switch to the East side of the Meridian and run the Polar Alignment Wizard again just to confirm I was
aligned there as well. To my surprise I was off by quite a bit (3 - 5 arc mins) East of the meridian after letting the drift
steps run for 3 - 5 mins. I didn't want to do any more ad justments as it took me several hours to get it to within 1 arc
min West of the meridian. I switched back to the West and ran the polar alignment wizard again for both Az and Alt
and after 5 mins both were still under 1 arc min. When I got to the step of moving the star to the end of the pointed
arrow I didn't have to do anything as they were both dead on the point of the arrow. All the PEMPro 3 settings I used
for where to slew in the sky where left at there defaults.

So my questions for the group is why would my polar alignment be different on one side of the meridian vs. the other? I
thought once the mount is polar aligned it really should not matter which side of the Pier it is on. I have no idea why
doing a pier flip to the other side of the meridian would cause such a big swing in the alignment. My only guess is that
maybe my OTA is not sitting Orthogonal on the mount but I wouldn't think it would matter for drift alignment. The other
thought I had is maybe I ne ed to adjust my balance to be slightly weights heavy. Currently it is almost perfectly
balanced on both axis. The Mach 1 is only about a year and half old so would not expect there to be much backlash as
it has the new self adjusting gear mesh mechanism.

Needless to say, I am kind of stumped. I would welcome any knowledgeable advice on what might be going on here
as I am not really sure what to do next.

Thanks in advance for the helpful advice.

Clear Skies,
Andrew J






Re: PemPro Polar Alignment differs East to West

Roland Christen
 

I went thru the same process with our remote scope in Chile several years ago. We had the polar alignment dead on with no movement in Dec for many minutes. The mount is a 1600 and scope was a 12" Mak-Cass astrograph. When we switched the scope to the other side and checked alignment on the west side, it was off, much to my amazement. In both cases the Dec axis was sitting still, not being driven. I have tried to simulate this motion via computer analysis, but no matter what changed, the alignment should remain exactly the same on either side of the axis. Even with the RA and Dec axes out of square the drift is still zero in both cases.

It then dawned on me that at the long focal length of the 12" scope, the effects of atmospheric refraction caused a small change in the star's declination. So on one side it drifts up slightly over time and on the other side it drifts down on the chip. I finally set the azimuth so that the drifts were equal on both sides rather than zero.

I might be totally wrong about this effect and its cause, but I have seen this on all the mounts that I have set up here at my observatory using PEMPRO polar alignment routine.

Rolando



-----Original Message-----
From: andrew.jones@... [ap-gto]
To: ap-gto
Sent: Sat, Mar 3, 2018 1:08 pm
Subject: [ap-gto] PemPro Polar Alignment differs East to West



Hello Everyone. I am looking for some guidance. I have a Mach 1 on a permanent pier in an observatory that I am in the process of getting setup. I currently have a 11" EdgeHD SCT mounted on the Mach 1. Last night I finally got around to getting my polar alignment dialed it. I have been using a PoleMaster to get me pretty close, but wanted to see if I could further refine the alignment using PemPro 3 since I had recently paid for the upgrade.

I started the PEMPro Alignment Wizard on the West side of the Meridian and did both the Azimuth and Altitude alignments several times until I got both under 1 arc min which was pretty much the limit of my Seeing last night. I then decided to switch to the East side of the Meridian and run the Polar Alignment Wizard again just to confirm I was aligned there as well. To my surprise I was off by quite a bit (3 - 5 arc mins) East of the meridian after letting the drift steps run for 3 - 5 mins. I didn't want to do any more adj ustments as it took me several hours to get it to within 1 arc min West of the meridian. I switched back to the West and ran the polar alignment wizard again for both Az and Alt and after 5 mins both were still under 1 arc min. When I got to the step of moving the star to the end of the pointed arrow I didn't have to do anything as they were both dead on the point of the arrow. All the PEMPro 3 settings I used for where to slew in the sky where left at there defaults.

So my questions for the group is why would my polar alignment be different on one side of the meridian vs. the other? I thought once the mount is polar aligned it really should not matter which side of the Pier it is on. I have no idea why doing a pier flip to the other side of the meridian would cause such a big swing in the alignment. My only guess is that maybe my OTA is not sitting Orthogonal on the mount but I wouldn't think it would matter for drift alignment. The other thought I had is may be I need to adjust my balance to be slightly weights heavy. Currently it is almost perfectly balanced on both axis. The Mach 1 is only about a year and half old so would not expect there to be much backlash as it has the new self adjusting gear mesh mechanism.

Needless to say, I am kind of stumped. I would welcome any knowledgeable advice on what might be going on here as I am not really sure what to do next.

Thanks in advance for the helpful advice.

Clear Skies,
Andrew J




Re: DEC delay in reversal

Roland Christen
 

You may have end play on the small worm. That is caused by the retaining nut being loose. If there is end play, you can feel it when you move the end of the telescope back and forth in the Dec direction. Try to gently move the scope back and forth with just finger pressure. If you feel a small amount of play at the end of the scope, you may have a loose bearing on the worm shaft.

You can remove the end play by unscrewing the small round cover on the right side of the gearbox, you will see the retaining nut with 2 small holes which are used with a spanner wrench. Use a spanner to first back off the nut turning counterclockwise, then tighten turning clockwise until the bearing is fully seated and you feel no more motion at the end of your scope.

Rolando


-----Original Message-----
From: Suresh Mohan Neelmegh drsureshmohan@... [ap-gto]
To: ap-gto
Sent: Sat, Mar 3, 2018 12:44 pm
Subject: [ap-gto] DEC delay in reversal

I’m getting a huge delay in reversal when I change direction, I opened the gear box to see where the delay is ; all the gears are working fine but the worm gear ( the huge one is taking time ; if i tighten a little on the harder side the motor is struggling. . What should I check ?
Suresh



------------------------------------
Posted by: Suresh Mohan Neelmegh <drsureshmohan@...>
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Re: APPM and Pinpoint

W Hilmo
 

I looked at the APPM log file, and it doesn’t have any additional information as to what happened with the plate solve. Actually, it considers the solve successful, which it was not (unless success is defined as “done”). Here is an excerpt:



---------------

0000034 2018-03-03 09:06:18.360: Info, PinPoint Test Solve, File = C:&#92;Users&#92;wadeh&#92;Desktop&#92;Cone-1x1800-Ha.fit

0000035 2018-03-03 09:06:18.360: Info, PinPoint Test Solve, RA/Dec = 6.66811666666667 / 9.64386944444444

0000036 2018-03-03 09:06:18.360: Info, PinPoint Test Solve, Use FITS for Hints = True, X/Y Scale = 1.62 / 1.62

0000037 2018-03-03 09:06:18.360: Info, PinPoint Test Solve, AllSky = False

0000038 2018-03-03 09:06:18.360: Info, PinPoint Test Solve, Timeout = 120

0000039 2018-03-03 09:08:27.650: Info, PinPoint Test Solve, Solve Successful

0000040 2018-03-03 09:08:31.421: Exception, Plate Solving, User Clicked Cancel or Close

---------------



Regarding a sample image, I don’t have a Dropbox account, but you can download a FITS file from https://www.faintfuzzy.net/2018/cone-1x1800-ha.fit. This is a wide field setup, so there are lots of stars. To solve it efficiently in Visual Pinpoint with USNO A2.0, I am using Min sigma of 8 and Max magnitude of 10. This one took 22 seconds when I tried it right now. My 2x2 binned images off the same system take about 5 or 6 seconds. Here is the output from Visual Pinpoint for this image and the above settings:

---------------

Plate-solve run at 3/3/2018 11:07:45 AM

Use File/Save As to save this file



&#92;&#92;xxx&#92;Cone-1x1800-Ha.fit:

3751 image stars found.

(doing spiral search...)

172 catalog stars found.

Solved using 50 of max 500, RMS residual is 0.50 arcsec, order =4

Solution took 22.8 seconds

Centerpoint RA = 06h 41m 03.766s Dec = 09° 37' 25.91"

Pointing error 0.3 arc minutes

WCS: Roll = -0.48 HScale = -1.622 VScale = -1.623

PA = 0.485°

FWHM = 6.39 arcsec

ZeroPoint = 16.44 (1 sec.)

---------------



Thanks,

-Wade







From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Saturday, March 3, 2018 10:38 AM
To: ap-gto@yahoogroups.com
Subject: RE: [ap-gto] APPM and Pinpoint





Is there any way to get either a more complete error message, or enable logging to get more details as to the progress of the attempt?
Yes, you can look at the APPM log file.



-Ray Gralak

Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc

Author of PEMPro: <http://www.ccdware.com/> http://www.ccdware.com

Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver

Author of PulseGuide: http://www.pulseguide.com <http://www.pulseguide.com/>

Author of Sigma: http://www..gralak.com/sigma <http://www.gralak.com/sigma>



From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Saturday, March 3, 2018 9:49 AM
To: ap-gto@yahoogroups.com
Subject: [ap-gto] APPM and Pinpoint





I am using APCC Pro (version 1.6.0.3) and have been using Pinpoint v6 as the plate solver for APPM. This has been working reasonably well for me with the GSC 1.1 catalog. Still, I do get some occasional plate solve failures, perhaps about 5% of the time. I have had it on my "to do" list for a while to switch to the USNO A2.0 catalog, and today is the day that I'm playing with it.





The problem that I am having is that APPM's Image Link Test fails all attempts at solving with this catalog.



Prior to testing with APPM, I worked with Visual Pinpoint to verify that the catalog works correctly. It is able to solve my test images in about 5 to 6 seconds. To get it working efficiently, I needed to tune the Min Sigma and Max Magnitude settings in Visual Pinpoint.



< p>I have matched these settings in the Sigma Above Mean and Catalog Max Mag settings in APPM. I have also verified that the coordinates and image scale from the FITS headers are correct when Image Link Test reports them.



The issue is that Image Link Test times out nearly 100% of the time on my test images. I bumped the Max Solve Time up to 120 seconds and it still times out. I have seen a couple of tests fail at about the 90 second point with an error that no stars were matched.



Is there any way to get either a more complete error message, or enable logging to get more details as to the progress of the attempt? In particular, Visual Pinpoint reports the number of image stars detected and the number of catalog stars found on both failed and successful solves. This would be very valuable information in troubleshooting this.



I'm also open to any other suggestions.



Thanks,

-Wade





[Non-text portions of this message have been removed]


PemPro Polar Alignment differs East to West

Andrew Jones
 

Hello Everyone. I am looking for some guidance. I have a Mach 1 on a permanent pier in an observatory that I am in the process of getting setup. I currently have a 11" EdgeHD SCT mounted on the Mach 1. Last night I finally got around to getting my polar alignment dialed it. I have been using a PoleMaster to get me pretty close, but wanted to see if I could further refine the alignment using PemPro 3 since I had recently paid for the upgrade.

I started the PEMPro Alignment Wizard on the West side of the Meridian and did both the Azimuth and Altitude alignments several times until I got both under 1 arc min which was pretty much the limit of my Seeing last night. I then decided to switch to the East side of the Meridian and run the Polar Alignment Wizard again just to confirm I was aligned there as well. To my surprise I was off by quite a bit (3 - 5 arc mins) East of the meridian after letting the drift steps run for 3 - 5 mins. I didn't want to do any more adjustments as it took me several hours to get it to within 1 arc min West of the meridian. I switched back to the West and ran the polar alignment wizard again for both Az and Alt and after 5 mins both were still under 1 arc min. When I got to the step of moving the star to the end of the pointed arrow I didn't have to do anything as they were both dead on the point of the arrow. All the PEMPro 3 settings I used for where to slew in the sky where left at there defaults.

So my questions for the group is why would my polar alignment be different on one side of the meridian vs. the other? I thought once the mount is polar aligned it really should not matter which side of the Pier it is on. I have no idea why doing a pier flip to the other side of the meridian would cause such a big swing in the alignment. My only guess is that maybe my OTA is not sitting Orthogonal on the mount but I wouldn't think it would matter for drift alignment. The other thought I had is maybe I need to adjust my balance to be slightly weights heavy. Currently it is almost perfectly balanced on both axis. The Mach 1 is only about a year and half old so would not expect there to be much backlash as it has the new self adjusting gear mesh mechanism.

Needless to say, I am kind of stumped. I would welcome any knowledgeable advice on what might be going on here as I am not really sure what to do next.

Thanks in advance for the helpful advice.

Clear Skies,
Andrew J



DEC delay in reversal

Suresh Mohan
 

I’m getting a huge delay in reversal when I change direction, I opened the gear box to see where the delay is ; all the gears are working fine but the worm gear ( the huge one is taking time ; if i tighten a little on the harder side the motor is struggling. . What should I check ?
Suresh


Re: APPM and Pinpoint

Ray Gralak
 

> Is there any way to get either a more complete error message, or enable logging to get more details as to the progress of the attempt? 

Yes, you can look at the APPM log file.

 

-Ray Gralak

Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc

Author of PEMPro:  http://www.ccdware.com

Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver

Author of PulseGuide: http://www.pulseguide.com

Author of Sigma: http://www.gralak.com/sigma

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, March 3, 2018 9:49 AM
To: ap-gto@...
Subject: [ap-gto] APPM and Pinpoint

 

 

I am using APCC Pro (version 1.6.0.3) and have been using Pinpoint v6 as the plate solver for APPM.  This has been working reasonably well for me with the GSC 1.1 catalog.  Still, I do get some occasional plate solve failures, perhaps about 5% of the time.  I have had it on my "to do" list for a while to switch to the USNO A2.0 catalog, and today is the day that I'm playing with it.



The problem that I am having is that APPM's Image Link Test fails all attempts at solving with this catalog.

 

Prior to testing with APPM, I worked with Visual Pinpoint to verify that the catalog works correctly.  It is able to solve my test images in about 5 to 6 seconds.  To get it working efficiently, I needed to tune the Min Sigma and Max Magnitude settings in Visual Pinpoint.

 

< p>I have matched these settings in the Sigma Above Mean and Catalog Max Mag settings in APPM.  I have also verified that the coordinates and image scale from the FITS headers are correct when Image Link Test reports them.

 

The issue is that Image Link Test times out nearly 100% of the time on my test images.  I bumped the Max Solve Time up to 120 seconds and it still times out.  I have seen a couple of tests fail at about the 90 second point with an error that no stars were matched.

 

Is there any way to get either a more complete error message, or enable logging to get more details as to the progress of the attempt?  In particular, Visual Pinpoint reports the number of image stars detected and the number of catalog stars found on both failed and successful solves.  This would be very valuable information in troubleshooting this.

 

I'm also open to any other suggestions.

 

Thanks,

-Wade


Re: APPM and Pinpoint

Ray Gralak
 

Hi Wade,

 

Can you zip some of the problem images and make them available via a dropbox link?

 

-Ray Gralak

Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc

Author of PEMPro:  http://www.ccdware.com

Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver

Author of PulseGuide: http://www.pulseguide.com

Author of Sigma: http://www.gralak.com/sigma

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, March 3, 2018 9:49 AM
To: ap-gto@...
Subject: [ap-gto] APPM and Pinpoint

 

 

I am using APCC Pro (version 1.6.0.3) and have been using Pinpoint v6 as the plate solver for APPM.  This has been working reasonably well for me with the GSC 1.1 catalog.  Still, I do get some occasional plate solve failures, perhaps about 5% of the time.  I have had it on my "to do" list for a while to switch to the USNO A2.0 catalog, and today is the day that I'm playing with it.



The problem that I am having is that APPM's Image Link Test fails all attempts at solving with this catalog.

 

Prior to testing with APPM, I worked with Visual Pinpoint to verify that the catalog works correctly.  It is able to solve my test images in about 5 to 6 seconds.  To get it working efficiently, I needed to tune the Min Sigma and Max Magnitude settings in Visual Pinpoint.

 

< p>I have matched these settings in the Sigma Above Mean and Catalog Max Mag settings in APPM.  I have also verified that the coordinates and image scale from the FITS headers are correct when Image Link Test reports them.

 

The issue is that Image Link Test times out nearly 100% of the time on my test images.  I bumped the Max Solve Time up to 120 seconds and it still times out.  I have seen a couple of tests fail at about the 90 second point with an error that no stars were matched.

 

Is there any way to get either a more complete error message, or enable logging to get more details as to the progress of the attempt?  In particular, Visual Pinpoint reports the number of image stars detected and the number of catalog stars found on both failed and successful solves.  This would be very valuable information in troubleshooting this.

 

I'm also open to any other suggestions.

 

Thanks,

-Wade


APPM and Pinpoint

W Hilmo
 

I am using APCC Pro (version 1.6.0.3) and have been using Pinpoint v6 as the plate solver for APPM.  This has been working reasonably well for me with the GSC 1.1 catalog.  Still, I do get some occasional plate solve failures, perhaps about 5% of the time.  I have had it on my "to do" list for a while to switch to the USNO A2.0 catalog, and today is the day that I'm playing with it.


The problem that I am having is that APPM's Image Link Test fails all attempts at solving with this catalog.


Prior to testing with APPM, I worked with Visual Pinpoint to verify that the catalog works correctly.  It is able to solve my test images in about 5 to 6 seconds.  To get it working efficiently, I needed to tune the Min Sigma and Max Magnitude settings in Visual Pinpoint.


I have matched these settings in the Sigma Above Mean and Catalog Max Mag settings in APPM.  I have also verified that the coordinates and image scale from the FITS headers are correct when Image Link Test reports them.


The issue is that Image Link Test times out nearly 100% of the time on my test images.  I bumped the Max Solve Time up to 120 seconds and it still times out.  I have seen a couple of tests fail at about the 90 second point with an error that no stars were matched.


Is there any way to get either a more complete error message, or enable logging to get more details as to the progress of the attempt?  In particular, Visual Pinpoint reports the number of image stars detected and the number of catalog stars found on both failed and successful solves.  This would be very valuable information in troubleshooting this.


I'm also open to any other suggestions.


Thanks,

-Wade


Re: A-P1100 Absolute Encoders installed by Astro-Physics?

Ray Gralak
 

Roland wrote:

Sure, you can do unguided imaging with a small refractor, even without absolute encoders. Just turn on PEM function,
drift align on the pole (or use pole scope, electronic pole finder etc) and fire away. When you have a 3 arc sec per pixel
imaging scale, you won't notice small drift errors. Once you go above about 500mm with a good sharp optical system
you better control your star motions to the sub-arc sec level. And you cannot do that with just good polar alignment
alone.
Roland makes a good point here that I didn't mention in my last post. You can usually get great results by just using PEM if you are using a short focal length refractor. Encoders will provide a more visible difference in a longer focal length scope.

Still, it wouldn't hurt at all to use encoders with a short focal length scope. It's just that the bang for the buck isn't as great in that case.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma


-----Original Message-----
From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Friday, March 2, 2018 6:38 PM
To: ap-gto@yahoogroups.com
Subject: Re: [ap-gto] Re: A-P1100 Absolute Encoders installed by Astro-Physics?




I thought the whole purpose of absolute encoders is to allow long exposures unguided with no periodic error.

There is no periodic error. That allows unguided imaging as long as you have no drift in either axis. However,
practically speaking there can always be some drift due to things not under the mount's control such as:

1) tube flexure or optical axis flex in the scope or imaging train
2) Polar misalignment
3) atmospheric refraction
4) other effects like mirror flop

Some of these things can be minimized, but others are inherent. Example, #3 - atmospheric refraction causes different
tracking rates in different parts of the sky, not only in RA but also in Dec, AND is not a fixed amount but varies with
atmospheric temperature and pressure.

Unguided imaging is possible with encoders because it eliminates the largest variable, the mount's periodic error. It
also enables a modeling program to set the delta tracking rates in both axes to a very fine resolution in order to counter
all the other variables.

Sure, you can do unguided imaging with a small refractor, even without absolute encoders. Just turn on PEM function,
drift align on the pole (or use pole scope, electronic pole finder etc) and fire away. When you have a 3 arc sec per pixel
imaging scale, you won't notice small drift errors. Once you go above about 500mm with a good sharp optical system
you better control your star motions to the sub-arc sec level. And you cannot do that with just good polar alignment
alone.

Rolando




-----Original Message-----
From: axnyslie@gmail.com [ap-gto] <ap-gto@yahoogroups.com>
To: ap-gto <ap-gto@yahoogroups.com>
Sent: Fri, Mar 2, 2018 8:16 pm
Subject: [ap-gto] Re: A-P1100 Absolute Encoders installed by Astro-Physics?




I thought the whole purpose of absolute encoders is to allow long exposures unguided with no periodic error. Seems
like a pricey upgrade if you still have to implement a guidescope or OAG in the imaging process.

Joe




Re: A-P1100 Absolute Encoders installed by Astro-Physics?

Ray Gralak
 

Hi Peter,

You wrote:

Yes, I forgot about that. PEMPro works best with good to excellent seeing condition and I don't want to deal with that.
Just a clarification here... PEMPro's PEC creation will work well even in poor seeing conditions. In fact it's because PEMPro can "see through" the effects of random or consistent poor seeing conditions that you would want to use PEMPro to create a smooth and accurate PEC curve over other PEC creation mechanisms.

That said, using high resolution absolute encoders like you can get for the AP1100/1600/3600 is a superior solution. They will not only correct periodic error but also non-periodic error caused by random variations in the worm wheel teeth on other factors. Encoders are definitely the way to go if you can afford them.

Best regards,

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma


-----Original Message-----
From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Friday, March 2, 2018 2:15 PM
To: ap-gto@yahoogroups.com
Subject: Re: [ap-gto] A-P1100 Absolute Encoders installed by Astro-Physics?



Yes, I forgot about that. PEMPro works best with good to excellent seeing condition and I don't want to deal with that.
AE does not care about seeing condition as long as the PE is always super low and smooth!!!!!!

Peter



---In ap-gto@yahoogroups.com, <bill@...> wrote :



Ditto on that.




Although PEMPro is pretty easy to use once you dig in and work with it. The sky is usually more challenging than
PEMPro is. 😉



________________________________

From: ap-gto@yahoogroups.com <ap-gto@yahoogroups.com> on behalf of 'Wade Hilmo' y.groups@... [ap-gto] <ap-
gto@yahoogroups.com>
Sent: Friday, March 2, 2018 2:02 PM
To: ap-gto@yahoogroups.com
Subject: RE: [ap-gto] A-P1100 Absolute Encoders installed by Astro-Physics?



Fair enough.

I have big respect for “because I can”. I’ve many things in my life for just that reason :)

-Wade

From: ap-gto@yahoogroups.com [mailto:ap-gto@yahoogroups.com]
Sent: Friday, March 2, 2018 1:44 PM
To: ap-gto@yahoogroups.com
Subject: RE: [ap-gto] A-P1100 Absolute Encoders installed by Astro-Physics?

Hi Wade,

It's more of laziness of my part. I don't feel like using PEMPro to reduce PE and I like the idea of having extremely low
PE and super smooth tracking in AE all the time despite the extra cost. PEC is not required or used with AE.

Most of all, it's because I can!!!!!

Peter

---In ap-gto@yahoogroups.com, <y.groups@...> wrote :

The weight of the AE kit is not significant, probably around 1lb. You won’t notice it.

I’m a bit curious, though, if your setup is always portable, what are you trying to achieve with the absolute encoders?

-Wade

From: ap-gto@yahoogroups.com <mailto:ap-gto@yahoogroups.com> [mailto:ap-gto@yahoogroups.com <mailto:ap-
gto@yahoogroups.com> ]
Sent: Friday, March 2, 2018 1:16 PM
To: ap-gto@yahoogroups.com <mailto:ap-gto@yahoogroups.com>
Subject: Re: [ap-gto] A-P1100 Absolute Encoders installed by Astro-Physics?

Rolando,

Another question about AE. What is the total weight of AE Kit for A-P1100 mount?

My setup is always portable and I carry the whole RA/Dec assembly (minus counterweight shaft) from inside of my
house to backyard (very short trip). I hope AE does not add too much weight to my A-P1100 mount.

Peter

---In ap-gto@yahoogroups.com <mailto:ap-gto@yahoogroups.com> , <pnagy@...> wrote :

Hi Rolando,

I live in Reno, NV and temperature can drop to as low as about 10F (-14C) and temperature is normally warmer than
20F (4C). I usually don't image if the forecast gets colder than 20F (4C) or if the dew point falls below ambient
temperature. Reno is generally pretty dry so I don't have electric dew shield. Anyway which temperature version AE do
you recommend for my area: Standard or Extended? I see the spec at your web site:

RESOLUTE Absolute Encoder:
Operating: 0 degrees C to +80 degrees C (32 F to +176 F)
Storage: -20 degrees C to +80 degrees C (-4 F to +176 F)
RESOLUTE ETR (Extended Temperature Range) Encoder:
Operating: -40 degrees C to +80 degrees C (-40 F to +176 F)<
Storage: -40 degrees C to +80 degrees C (-40 F to +176 F)

Thanks,

Peter

[Non-text portions of this message have been removed]

[Non-text portions of this message have been removed]




Re: Encoder assembly video

Gregory <fyrframe@...>
 

On 3/2/2018 3:17 PM, chris1011@... [ap-gto] wrote:
 

Hi All,

We shot a series of video snips showing how to assemble the encoder to the 1100 mount. I was hoping to post it up, but it needs to be edited into one continuous video (which i don't know how to do but we'll figure it out). So hang in there.

Rolando



Re: A-P1100 Absolute Encoders installed by Astro-Physics?

Roland Christen
 


I thought the whole purpose of absolute encoders is to allow long exposures unguided with no periodic error.
There is no periodic error. That allows unguided imaging as long as you have no drift in either axis. However, practically speaking there can always be some drift due to things not under the mount's control such as:

1) tube flexure or optical axis flex in the scope or imaging train
2) Polar misalignment
3) atmospheric refraction
4) other effects like mirror flop

Some of these things can be minimized, but others are inherent. Example, #3 - atmospheric refraction causes different tracking rates in different parts of the sky, not only in RA but also in Dec, AND is not a fixed amount but varies with atmospheric temperature and pressure.

Unguided imaging is possible with encoders because it eliminates the largest variable, the mount's periodic error. It also enables a modeling program to set the delta tracking rates in both axes to a very fine resolution in order to counter all the other variables.

Sure, you can do unguided imaging with a small refractor, even without absolute encoders. Just turn on PEM function, drift align on the pole (or use pole scope, electronic pole finder etc) and fire away. When you have a 3 arc sec per pixel imaging scale, you won't notice small drift errors. Once you go above about 500mm with a good sharp optical system you better control your star motions to the sub-arc sec level. And you cannot do that with just good polar alignment alone.

Rolando



-----Original Message-----
From: axnyslie@... [ap-gto]
To: ap-gto
Sent: Fri, Mar 2, 2018 8:16 pm
Subject: [ap-gto] Re: A-P1100 Absolute Encoders installed by Astro-Physics?



I thought the whole purpose of absolute encoders is to allow long exposures unguided with no periodic error. Seems like a pricey upgrade if you still have to implement a guidescope or OAG in the imaging process.

Joe



Re: A-P1100 Absolute Encoders installed by Astro-Physics?

axnyslie@...
 

I thought the whole purpose of absolute encoders is to allow long exposures unguided with no periodic error. Seems like a pricey upgrade if you still have to implement a guidescope or OAG in the imaging process.

Joe


Re: A-P1100 Absolute Encoders installed by Astro-Physics?

Roland Christen
 

Weight is less than 1 lb. per axis.

Rolando



-----Original Message-----
From: pnagy@... [ap-gto]
To: ap-gto
Sent: Fri, Mar 2, 2018 7:49 pm
Subject: Re: [ap-gto] A-P1100 Absolute Encoders installed by Astro-Physics?



Rolando,

Another question about AE. What is the total weight of AE Kit for A-P1100 mount?

My setup is always portable and I carry the whole RA/Dec assembly (minus counterweight shaft) from inside of my house to backyard (very short trip). I hope AE does not add too much weight to my A-P1100 mount.

Peter


---In ap-gto@..., wrote :

Hi Rolando,

I live in Reno, NV and temperature can drop to as low as about 10F (-14C) and temperature is normally warmer than 20F (4C). I usually don't image if the forecast gets colder than 20F (4C) or if the dew point falls below ambient temperature. Reno is generally pretty dry so I don't have electric dew shield. Anyway which temperature version AE do you recommend for my area: Standard or Extended? I see the spec at your web site:

RESOLU TE Absolute Encoder:
Operating: 0 degrees C to +80 degrees C (32 F to +176 F)
Storage: -20 degrees C to +80 degrees C (-4 F to +176 F)
RESOLUTE ETR (Extended Temperature Range) Encoder:
Operating: -40 degrees C to +80 degrees C (-40 F to +176 F)<
Storage: -40 degrees C to +80 degrees C (-40 F to +176 F)

Thanks,
Peter



Re: Encoder assembly video

topboxman
 

Hi Rolando,

Take your time.

Peter