×

INDI Library v1.9.6 Released (21 May 2022)

Bi-monthly INDI Library released with new drivers and bug fixes.

Cont. problem with guiding: Scope cannot reach the start point with RA reverse

  • Posts: 149
  • Thank you received: 10
Hi,

I have a continuous problem with the guiding calibration. Most of the time, the guiding fails while calibrating the RA axis and reverse drifting.

I use the Skywatcher EQ-6 mount, guiding with an ASI 290MC on an APM Imagemaster 50/240 guiding scope.

I did polar alignment previously, the polar alignment tool reports an polar error of 42 arc secs.

I am not really familiar with the guiding parameters and appreciate any hints or tips & tricks on how to get the guiding as reliable as the focussing :-)

Logs are attached

File Attachment:

File Name: log_22-28-29.txt.zip
File Size:1,243 KB
Skywatcher Newton 200/1000, Sharpstar 60ED, Canon Lenses
Skywatcherr EQ-6 R, AZ-GTI
StellarMate @ Raspberry Pi 3B+
ASI 183 MC Pro
ASI 290 MC guiding cam on APM 60 ImageMaster
Sesto Senso 2 Focuser + Astromechanics Canon Focuser

1 year 9 months ago #59593
Attachments:

Please Log in or Create an account to join the conversation.

  • Posts: 814
  • Thank you received: 394
Thanks for the report.

Sorry, I don't quite understand the log. I believe you didn't send the full log (usually the log starts with something like welcome to Kstars, so I could see which version of the software you're running).
Could you please send the full log (or point to it on a google drive link or something like that) and also send a picture of all the settings you're using--in the guide page, click on Options in the lower right corner
and take a screenshot of the Guide and Calibration sections of those options. Also, please let me know what software you're running.
I'd be happy to try and help out.

One last thing, there's a guide log that might be helpful. You can find that in a directory parallel to main logging directory, called guidelogs
and you'd find the guidelog that corresponds to whatever log you send.

Thanks,
Hy
AP1100 & Orion Atlas Pro, WO/ZS105 w/Moonlight V2 focus, GSO RC10 w/RSF focus
ZWO ASI1600, Astronomik Filters, ST80, QHY 5L-IIm.
KStars/Ekos/Indi on NUC10 & RPi4 w/SSD -- Ubuntu
Projects: Greedy Scheduler, Terrain, Polar Align, Analyze, Linear Focuser, SEP MultiStar & GPG Guide, FITS autostretch.
1 year 9 months ago #59608

Please Log in or Create an account to join the conversation.

  • Posts: 149
  • Thank you received: 10
Thank you Hy for your offer to help, much appreciated. I started logging in the middle of the session, therefore the log looks incomplete.

I will have clear skies tonight and will start logging from the very start and also take screenshots of the requested dialogs.

I am using version 3.4.3 of KStars, attached the first lines from my start right now.

Also attached the guide log of yesterday.

File Attachment:

File Name: guide_log-...6-06.txt
File Size:34 KB



[2020-09-09T10:17:10.551 CEST INFO ][ org.kde.kstars] - Welcome to KStars 3.4.3
[2020-09-09T10:17:10.551 CEST INFO ][ org.kde.kstars] - Build: 2020-07-18T05:21:35Z
[2020-09-09T10:17:10.553 CEST INFO ][ org.kde.kstars] - OS: "osx"
[2020-09-09T10:17:10.553 CEST INFO ][ org.kde.kstars] - API: "x86_64-little_endian-lp64"
[2020-09-09T10:17:10.554 CEST INFO ][ org.kde.kstars] - Arch: "x86_64"
[2020-09-09T10:17:10.554 CEST INFO ][ org.kde.kstars] - Kernel Type: "darwin"
[2020-09-09T10:17:10.554 CEST INFO ][ org.kde.kstars] - Kernel Version: "19.6.0"
[2020-09-09T10:17:10.554 CEST INFO ][ org.kde.kstars] - Qt Version: 5.14.2
Skywatcher Newton 200/1000, Sharpstar 60ED, Canon Lenses
Skywatcherr EQ-6 R, AZ-GTI
StellarMate @ Raspberry Pi 3B+
ASI 183 MC Pro
ASI 290 MC guiding cam on APM 60 ImageMaster
Sesto Senso 2 Focuser + Astromechanics Canon Focuser

1 year 9 months ago #59611
Attachments:

Please Log in or Create an account to join the conversation.

  • Posts: 380
  • Thank you received: 113
Assuming your mount drive parameters are right, have you ruled out weight balance as an issue? Some mounts are pretty difficult to achieve correct balance by just loosening clutches and watching scope moves during setup. If not right, it will definitely show during calibration. If you're not sure, I suggest the following:

Let's say for discussion purposes you are imaging in the east (weights on the east side of pier/tripod). If you can't get RA reverse calibration to behave, it might imply you have too much west weight (i.e. you need to move weights down a bit on the shaft). If you are struggling while imaging west (weights on west side), it would mean you need to slide weights up the shaft. The amount to move is subtle and specific to your gear. If you want to experiment, don't get carried away. Try to remember where you started, make small weight adjustment(s) on the shaft, and then test calibration again. If balance is the issue, you'll notice that responses (how far each calibration step gets) will change. You might have less distance response in forward RA, but start picking up reverse motion that you don't currently have. With a couple of tests, you should get a good feel for weight sensitivity on calibration. In the end, the balance goal should be very slightly east heavy (keeps a load on the drive while minimizing oscillation). This trick works for RA and DEC. Anyway, something easy to try as you continue debugging. Good luck!
RASA11, Celestron CGX-L, ASI183mc Pro, 60mm guider + ASI290mm mini, ASI EAF focuser, PPB, Rpi4-4Gb+SSD, Powered USB3 hub, hardwire Ethernet.
1 year 9 months ago #59622

Please Log in or Create an account to join the conversation.

  • Posts: 149
  • Thank you received: 10
Hello dmsummers,

thank you for the detailed hints. I just tested the balancing of the mount and I set it to equal weights on the RA axis as you can see in the photo. Maybe I am a bit dumb at this, but when I turn the setup around this axis it always moves counterclockwise, regardless if I let it go with the weight to the east or the west.



Three additional questions though:

1.) When calibration yesterday actually finished once, I was able to decently guide within 3 arc secs tolerance, so I assume the actual setup was not too bad. Is that correct?

2.) I can actually not balance the DEC axis as I can't move the setup that much to the front with the short dove tail plate. Do you recommend getting a bigger one to be able to balance DEC as well?

3.) Where can I see the calibration steps, you mentioned?

Sorry for the basic questions, hopefully that helps other board members as well to solve similar challenges.
Skywatcher Newton 200/1000, Sharpstar 60ED, Canon Lenses
Skywatcherr EQ-6 R, AZ-GTI
StellarMate @ Raspberry Pi 3B+
ASI 183 MC Pro
ASI 290 MC guiding cam on APM 60 ImageMaster
Sesto Senso 2 Focuser + Astromechanics Canon Focuser

Last edit: 1 year 9 months ago by Amin Sharaf.
1 year 9 months ago #59626
Attachments:

Please Log in or Create an account to join the conversation.

  • Posts: 1941
  • Thank you received: 416
2] Yes, get a bigger dove tail. Balance is crucial on both axes. With my HEQ5 I get guiding RMS well below 1” on both axes so it is worth it.
3] To the lower left is a drift plot. It is in a tab and one of the other tabs is the calibrarion plot.

HTHt, Wouter
Wouter van Reeven

ASI6200MM and 7 slot 2" filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro
ASI1600MM-Pro Cooled and 5 slot 1.25" filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R
1 year 9 months ago #59627

Please Log in or Create an account to join the conversation.

  • Posts: 149
  • Thank you received: 10
Hello Wouter,

thanks a lot, I managed to balance both axes now using the dove tail of my Newton. Thanks also for the hint to the calibration info.

I will try again tonight and report back.

Skywatcher Newton 200/1000, Sharpstar 60ED, Canon Lenses
Skywatcherr EQ-6 R, AZ-GTI
StellarMate @ Raspberry Pi 3B+
ASI 183 MC Pro
ASI 290 MC guiding cam on APM 60 ImageMaster
Sesto Senso 2 Focuser + Astromechanics Canon Focuser

The following user(s) said Thank You: Joaquin
1 year 9 months ago #59629
Attachments:

Please Log in or Create an account to join the conversation.

  • Posts: 380
  • Thank you received: 113
I agree with Wouter that balance in both axes should be the goal. Seems you have it now (although maybe you could redistribute or dead-weight your orig dovetail if you need the other one elsewhere?). About the calibration steps, besides the cal plot, you can look in the guidelog (can't remember if you need to enable verbose & file mode or not). The calibration section of the log will show the step size magnitudes. I use PHD, but the internal guider has a similar plot/log
RASA11, Celestron CGX-L, ASI183mc Pro, 60mm guider + ASI290mm mini, ASI EAF focuser, PPB, Rpi4-4Gb+SSD, Powered USB3 hub, hardwire Ethernet.
Last edit: 1 year 9 months ago by Doug S.
1 year 9 months ago #59630
Attachments:

Please Log in or Create an account to join the conversation.

  • Posts: 149
  • Thank you received: 10
With the last photo I sent the setup is actually balanced in both axes now. I will give it a try tonight again.
Skywatcher Newton 200/1000, Sharpstar 60ED, Canon Lenses
Skywatcherr EQ-6 R, AZ-GTI
StellarMate @ Raspberry Pi 3B+
ASI 183 MC Pro
ASI 290 MC guiding cam on APM 60 ImageMaster
Sesto Senso 2 Focuser + Astromechanics Canon Focuser

1 year 9 months ago #59632

Please Log in or Create an account to join the conversation.

  • Posts: 149
  • Thank you received: 10
Guys, thanks a lot.

After balancing out both axes it works like a charm stable and reliable for more than an hour tonight. Calibration went through the process in a few seconds and I am currently taking 5 min exposures with a guiding deviation around 1,5"

Your help was much appreciated!

best regards

Amin
Skywatcher Newton 200/1000, Sharpstar 60ED, Canon Lenses
Skywatcherr EQ-6 R, AZ-GTI
StellarMate @ Raspberry Pi 3B+
ASI 183 MC Pro
ASI 290 MC guiding cam on APM 60 ImageMaster
Sesto Senso 2 Focuser + Astromechanics Canon Focuser

1 year 9 months ago #59644

Please Log in or Create an account to join the conversation.

  • Posts: 149
  • Thank you received: 10
Hello,

after all your help, I wanted to share the first fruits with you as well.

Soul Nebula taken with the ASI 183 MC PRO on my reduced 60ED with the IDAS LPS filter, 50 x 300 secs.

Tanks again, best regards

Amin

Skywatcher Newton 200/1000, Sharpstar 60ED, Canon Lenses
Skywatcherr EQ-6 R, AZ-GTI
StellarMate @ Raspberry Pi 3B+
ASI 183 MC Pro
ASI 290 MC guiding cam on APM 60 ImageMaster
Sesto Senso 2 Focuser + Astromechanics Canon Focuser

Last edit: 1 year 9 months ago by Amin Sharaf.
1 year 9 months ago #60303
Attachments:

Please Log in or Create an account to join the conversation.

Time to create page: 0.319 seconds