Welcome, Guest
Username: Password: Remember me
25 Jul 2018
Glad to announce of release of INDI Library v1.7.4 on 2018-07-25. A few drivers were added in this release as we continue to improve & stabilize existing drivers.
  • Page:
  • 1

TOPIC: Mount Debugging

Mount Debugging 5 months 2 weeks ago #25723

  • fewayne
  • fewayne's Avatar Topic Author
  • Offline
  • Fresh Boarder
  • Fresh Boarder
  • Posts: 2
  • Thank you received: 0
Yes, I have engaged in an expedition to scale Mount Debugging almost every time I visit ProgrammerLand. :-)

I am trying to better polar-align my iOptron CEM25P. I have been using the Polar Alignment Assistant (hereinafter PAA) feature in Ekos. Cool tool!

Except that when I go off and guide, I am not getting better results. In fact PHD's Guide Assistant estimates my polar alignment error to be bigger than the initial error shown by the Ekos tool before I corrected, and indeed going back and running the Ekos tool afterwards seems to yield results almost as bad. Too, if I squint again through the polar scope after the process, Polaris is nowhere near where it's supposed to be on the reticle.

I'm at the hypothesis-generating stage, would love to hear some others.
  1. You totally kicked the tripod. (Really, I didn't.)
  2. The tripod settled into the ground over time. (It was on a concrete driveway.)
  3. The Fortune Cookie Reveal -- like a fortune cookie that reports "What you just ate wasn't really chicken", maybe that wasn't Polaris in the polar scope? (It was. Honest.)
  4. I didn't get the star close enough to the indicated dot (but if I do two PAA runs in succession, the second says I'm at least as good as the first)
  5. I should have slewed the scope in DEC away from the Pole, to sweep out a larger sky area for the PAA's capture/solves
  6. It took me too long to adjust onto the dot, so that the star had rotated away from its original position
#6 is at least plausible, given that it takes over 20 seconds between the start of a DSLR exposure and refreshing the screen, the adjustment takes at least 5 minutes. I could use the guidescope instead of the main scope, and buy much much faster refreshes at the cost of some precision (162mm F/L vs. 332mm, but a smaller sensor on the guidescope). The fact that the guidescope is never perfectly coaxial with the main scope should not matter -- right? It's the difference between the images that allows the PAA to calculate the actual alignment.

Any other ideas? TIA!

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

Last Edit: by fewayne.

Mount Debugging 5 months 2 weeks ago #25777

  • Ihoujin
  • Ihoujin's Avatar
  • Offline
  • Platinum Boarder
  • Platinum Boarder
  • Posts: 353
  • Karma: 1
  • Thank you received: 45
Use your guide scope, The refresh rates alone are worth it. Being a little out of collimation is fine, the procedure is only interested in the center of rotation, not what is effectively cone error.

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

INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
  • Page:
  • 1
Time to create page: 0.267 seconds


3rd Party

Choose from the numerous 3rd party INDI drivers to suit your needs!

Got Problem?

Check out the FAQ, the forum, and the bug tracking system to resolve any issues you might have!
You can also subscribe to INDI newsletter and development mailing lists to get the latest updates on INDI!