PHD2 Calibration NEQ6 PRO

[chriscoles]

Hi There, last night I calibrated PHD2 on my NEQ6. This calibration allowed guiding within two pixels. I think it can do better.

Can anyone see any likely causes of the bad calibration from the image? In particular the strange bump in the DEC.

My equipment is well balanced on bot RA and DEC. The backlash screws are set fairly well, I tried to get it as low as possible while allowing the motors to move freely.

I have a permanent set up in my roll off roof observatory so looking to get this tweaked!

Guide Camera: Celestron Skyris 445C

Guide Scope: 50mm aperture 190mm focal refractor

Main Scope: Celestron C11 SCT

Thanks in advance!

 

[geeklee]

Hi @chriscoles.  Is the guide speed on 0.1x on purpose?  This is usually the default being pulled from a standard EQASCOM mount configuration.  PHD2 recommends at least 0.5x.  There's a great best practice PDF document here, that might be worth a look:

https://openphdguiding.org/phd2-best-practices/ 

Apologies if you have this set on purpose 🙂  It just looks exactly like my first PHD2 session and once I'd upped the guide speed a lot more, the calibration (at least) looked much better.

Secondly,  did you use the brain icon to ensure your guide step is matched as per your camera settings?  The calculator options gives you a guide step in ms to enter.

[chriscoles]

Hey Geeklee, thanks for your reply!! I have read the best practice guide however overlooked the guide rate. I wonder why EQAASCOM defaults to 0.1? I have increased to 0.5 and will try again.

The camera is set up correctly as far as I can tell.

I will update this post when the cloud clears.

[geeklee]

38 minutes ago, chriscoles said:

Hey Geeklee, thanks for your reply!! I have read the best practice guide however overlooked the guide rate. I wonder why EQAASCOM defaults to 0.1? I have increased to 0.5 and will try again.

The camera is set up correctly as far as I can tell.

I will update this post when the cloud clears.

Hopefully that makes a difference.  Here's the section I mentioned above about camera setup, calibration steps and calibration step (ms)

The advanced button brings out the calibration parameters that you can check and then the step (ms) can be entered into the first screen (I'm not sure if it should auto populate, but mine doesn't)

If your calibration is taking about 11-13 steps (has 12 above) then it should be on course to complete as expected.  Here's a recent one from a similar mount (AZ EQ6) although slightly higher Declination than I should have used...

Edited December 31, 2019 by geeklee

[chriscoles]

Hey Geeklee! Thanks to your help, my guiding is all up and running.  The calibration works well with the rates changed to 0.5 and guiding is about 1/2 a pixel accurate. Now guiding is working, I can move on to my other issues