PHD2 RA guiding not reversing after meridian flip

[Andy56]

Hi

The title says it all.

I've Google'd this and searched forums but all I seem to find is Dec reversals.

So I'm using an HEQ5+ Guide Scope PHD2 and APT and ASTAP. I calibrate PHD2 and it guides correctly.

I if slew over the meridian or (using APT) do an automatic meridian flip, the RA guiding nudges it in the wrong direction.

If I then do a re-calibrate then all is OK.

I can't find anything that tells the system to compensate for this.

I have read that some mounts have meridian side detection and I guess there's a simple tick box somewhere that compensates for this.

So can someone point me in the right direction about this.

TIA

Andy

Edited November 14, 2022 by Andy56

[knobby]

Are you sure it's RA ?

[newbie alert]

Do you pulse or st4 guide? 

On older versions of PhD there used to be a guide north, south or auto in the bottom right corner

If pulse guiding you can calibrate both sides of peir

[Andy56]

Hi,

knobby: Yes it's RA as shown by PHD2. I note that the calibration is at 45deg. I don't know if this plays a part. Also the Reverse Dec output after Meridian Flip is ticked.

I've attached the log for anyone's perusal. Its at 2022-11-12 18:36:03 that shows the issue. This is just after moving from M31 to the Eastern Veil so crossing the meridian. See below:

It's happened many times before but I want to use AMS and this will need to work if I leave it unattended. 

 

 

Newbie: I'm using 2.6.11 which does not appear to have that option. It's ST4 as I'm using a cable from the ASI120mm mini to the mount.

 

Cheers

Andy

PHD2_GuideLog_2022-11-12_180035.txt

Edited November 14, 2022 by Andy56
A little more explanation and some grammar corrections

[Starflyer]

I think it you're using ST4 you need to recalibrate on every target change anyway. Any reason you're not using pulse guiding, it's just set and forget once you have a good calibration?

[alacant]

2 hours ago, Andy56 said:

It's ST4 as I'm using a cable from the ASI120mm mini to the mount.

the log confirms this:

Quote

Mount = On Camera, connected, guiding enabled, xAngle = -125.2, xRate = 1.250, yAngle = 144.8, yRate = 1.676, parity = ?/?

So you must calibrate after each mount slew; new target and/or meridian flip.

Recommendation +1 as @Starflyer: lose the on-camera cable and connect the mount to the computer with an eqdir cable. Much easier.

cheers and HTH

[Andy56]

OK.

"So you must calibrate after each mount slew; new target and/or meridian flip." Is this what causes the reversal of the RA guiding or is it to ensure best guiding?

 

I'm using ST4 because that's what I came across first and set it up this way. Also it's how I guide in RA only on a Star Adventurer.

Losing the cable would be great.

Currently I'm using a home made Blue Tooth connection to the HEQ5 control port. I guess this is the eqdir interface mentioned.

How do I enable Pulse Guiding. Just looked through PHD2, can't find pulse guiding. Is there a guide to this somewhere I can read?

 

Cheers

Andy

 

 

[alacant]

12 hours ago, Andy56 said:

 eqdir interface mentioned

Remove the camera to mount cable and connect the mount to the computer using this.

12 hours ago, Andy56 said:

How do I enable Pulse Guiding

It's a lot of extra software to have to manage, so if you're satisfied with your (very good as it is) guiding, stay with the old st4 simplicity and just get your automation app to reset the calibration after each mount slew. Make sure though to have several replacement camera to mount cables on hand;)

Or...

- Install ASCOM or (IMHO better) INDI.

- Install EQASCOM or (IMHO better) indi_eqmod

- Make a new PHD2 profile

- Rather than specify 'on camera' for the mount, choose 'HEQ5/6' or 'eqmod mount'.

12 hours ago, Andy56 said:

Is there a guide to this somewhere I can read?

PHD2 --> Help --> Contents:

Edited November 15, 2022 by alacant

[Andy56]

Now I've got I think.

alacant:

"Remove the camera to mount cable and connect the mount to the computer using this." I already have a bluetooth link.

I'm already running  ASCOM and EQASCOM for mount control through APT.

"Rather than specify 'on camera' for the mount, choose 'HEQ5/6' or 'eqmod mount'." This presumably changes it to pulse guiding.

I'd done a search on the PHD2 Help file for "pulse" but it returned no results so I'm assuming its not referred to as pulse guiding. I've had another look through and found it's referred as "pulseguide" so my original search did not find it.

I'll hook up the mount and give it a try on the next clear evening. So maybe next year LOL.

Many thanks

Andy

 

 

 

[alacant]

37 minutes ago, Andy56 said:

I'm already running  ASCOM

Ah, ok. So all you need to do is add an 'aux mount' entry so that phd2 knows where the telescope is pointing. 

 

[Starflyer]

On 15/11/2022 at 14:48, Andy56 said:

I'd done a search on the PHD2 Help file for "pulse" but it returned no results so I'm assuming its not referred to as pulse guiding. I've had another look through and found it's referred as "pulseguide" so my original search did not find it.

You need to enable pulse guiding in the EQMOD setup, see the second image in the NINA help page.

Also check the pulse guide rate on the right hand side of the normal EQMOD page, set it to 0.5 - 0.8.

Create a new profile in PHD2 and use the wizard to populate the information, make sure that the guidescope focal length and pixel size are correct.  To get the best calibration I do the following; in PHD2 go to Tools - Drift Align and press slew, once the slew had finished close the Drift Align tool, this has taken you to the best area in the sky to run the calibration, perform your calibration.