PHD2 calibration issues

[StuartT]

I am finding that when I calibrate (first pointing to the equator) I get an error saying 'not enough calibration steps - results may be inaccurate'.

This is the log viewer diagram. Surely if there aren't enough steps PHD2 could just do more? What's stopping it?

[Starflyer]

The calibration works over 25 pixels and afaik that's set and can't be changed.  I aim for about 12 steps, you're getting four or five steps at 1050ms calibration step size, try dropping it to 350ms, that should sort it out.

[StuartT]

46 minutes ago, Starflyer said:

The calibration works over 25 pixels and afaik that's set and can't be changed.  I aim for about 12 steps, you're getting four or five steps at 1050ms calibration step size, try dropping it to 350ms, that should sort it out.

Thanks. I find PHD2 to be somewhat impenetrable to be honest. I've tried reading the documentation but it makes very little sense to me. I didn't even realise you could change the calibration process! 

I'll give this a try 

[newbie alert]

The settings etc all used to be accessible from the brain tab on the older versions, it's fairly easy to find although I could tell you exactly where it is  now without looking at PhD .. once you get the hang of PhD it's fairly straightforward and hassle free..

[alacant]

11 hours ago, StuartT said:

What's stopping it?

The settings you have given for PHD2 to work with.

It looks like you've entered the focal length of your imaging telescope, 808mm, rather than your guide telescope.
With camera and mount connected,  make a new profile. Be sure to enter only what it asks. Change nothing.

Cheers and HTH

[knobby]

Stuart uses an oag I believe.

As suggested by Starflyer, try lowering step size.

[StuartT]

3 hours ago, alacant said:

The settings you have given for PHD2 to work with.

It looks like you've entered the focal length of your imaging telescope, 808mm, rather than your guide telescope.
With camera and mount connected,  make a new profile. Be sure to enter only what it asks. Change nothing.

Cheers and HTH

I don't use a guide scope. My understanding was that with an OAG you should use the FL of the imaging scope, no?

I always use the new profile wizard to make a profile. And did so in this case too - it's captured the various details (e.g. pixel size of the guide cam) correctly, so if a step size of 1050ms is indeed wrong  (as others have pointed out) then I am puzzled. I've not changed any settings  

Edited February 2, 2023 by StuartT

[newbie alert]

1 hour ago, StuartT said:

I don't use a guide scope. My understanding was that with an OAG you should use the FL of the imaging scope, no?

Yes you do

[knobby]

3 hours ago, StuartT said:

I don't use a guide scope. My understanding was that with an OAG you should use the FL of the imaging scope, no?

I always use the new profile wizard to make a profile. And did so in this case too - it's captured the various details (e.g. pixel size of the guide cam) correctly, so if a step size of 1050ms is indeed wrong  (as others have pointed out) then I am puzzled. I've not changed any settings  

PHD2 makes assumptions about your equipment, usually correct but not always due to manufacturing variances.

And yes, you use the main scope length if using an oag.

[michael8554]

As you're using EQMOD, to get more Calibration steps you should adjust the "EQMOD ASCOM PulseGuide setting", which seems to be a multiplier to the mount's guide rate setting of 12 arcsec/sec..

Don't alter the PHD2 Cal Step size.

As that has been correctly calculated from the settings you entered in the wizard.

Michael

[StuartT]

On 01/02/2023 at 19:47, Starflyer said:

The calibration works over 25 pixels and afaik that's set and can't be changed.  I aim for about 12 steps, you're getting four or five steps at 1050ms calibration step size, try dropping it to 350ms, that should sort it out.

 

3 hours ago, michael8554 said:

Don't alter the PHD2 Cal Step size.

=======================================

 

So now I have two directly contradictory pieces of advice.

reduce guide step size

dont reduce guide step size

🤔

 

Edited February 2, 2023 by StuartT

[whipdry]

2 hours ago, StuartT said:

On 01/02/2023 at 19:47, Starflyer said:

The calibration works over 25 pixels and afaik that's set and can't be changed.  I aim for about 12 steps, you're getting four or five steps at 1050ms calibration step size, try dropping it to 350ms, that should sort it out.

 

3 hours ago, michael8554 said:

Don't alter the PHD2 Cal Step size.

=======================================

 

So now I have two directly contradictory pieces of advice.

reduce guide step size

dont reduce guide step size

🤔

 

It may seem like a conflict but they are just suggesting you change setting in different places... in Phd2 less ms per move or in EQ Mode adjust (slow down try x0.5) the mounts guide speed... try them both & see which works best for you. 

 

Peter

[michael8554]

I see you've posted on the PHD2 Help Forum  😆

Please Keep us posted.

Michael

[david_taurus83]

Are you using the latest developer version?

I had issues this week with PHD calibration. When I'm pointed to Dec 0 I always click on the brain button, go into the guide tab and reset the steps. It usually goes to 500 steps or so but after experiencing issues, mount not moving, PHD hanging etc when I tried to reset as above again, the steps always defaulted to 10000. If I remember correctly PHD offered a recent update to the developer version...

I installed the normal version and my problem went away.

[StuartT]

1 hour ago, david_taurus83 said:

Are you using the latest developer version?

I had issues this week with PHD calibration. When I'm pointed to Dec 0 I always click on the brain button, go into the guide tab and reset the steps. It usually goes to 500 steps or so but after experiencing issues, mount not moving, PHD hanging etc when I tried to reset as above again, the steps always defaulted to 10000. If I remember correctly PHD offered a recent update to the developer version...

I installed the normal version and my problem went away.

That's interesting. Yes, I am using the dev version. In fact I was advised to by the people on the PHD2 google group. Maybe that's the issue then. I shall 'roll back' and give it another try. Thank you!

[StuartT]

On 03/02/2023 at 09:19, michael8554 said:

I see you've posted on the PHD2 Help Forum  😆

Please Keep us posted.

Michael

They said (I think) that you can change either. But I am going to try your method (reducing the guide rate in EQASCOM). Presumably this means I shall need to create a new profile in PHD2 though? (since PHD2 reads details from the mount?) Thanks

[michael8554]

My thought was:

If the PHD2 setting is correct, and the EQMOD setting wrong, which one would you correct ?

You don't need to make a new PHD2 Profile .

PHD2 still correctly reads the guide speed that is set in the mount .

But during the Cal discovers that the actual guide rates are very different, due to EQMOD.

I've no idea why EQMOD needs that setting that initially catches out many users.

Michael

Edited February 5, 2023 by michael8554

[Skipper Billy]

You might find the second document down on this page of my website useful.....

Astro-Imaging - 'How To' (davidbanksastro.com)

[Stuart1971]

14 hours ago, StuartT said:

They said (I think) that you can change either. But I am going to try your method (reducing the guide rate in EQASCOM). Presumably this means I shall need to create a new profile in PHD2 though? (since PHD2 reads details from the mount?) Thanks

What guiding rate are you using at present, I used to use 0.9x with my EQ8, as recommended by the NINA gurus, but had issues, so dropped it to 0.5 and all was good… GSS the driver i use now, have always said to start at 0.5, and up it if required…but I never needed to

Edited February 5, 2023 by Stuart1971

[Stuart1971]

4 minutes ago, Stuart1971 said:

On 01/02/2023 at 19:15, StuartT said:

I am finding that when I calibrate (first pointing to the equator) I get an error saying 'not enough calibration steps - results may be inaccurate'.

This is the log viewer diagram. Surely if there aren't enough steps PHD2 could just do more? What's stopping it?

Get rid of the bug filled DEV version and stick to the release version, or you will have nothing but issues and headaches, I never understand why people use DEV or beta versions and then wonder why they have issues, it’s just not worth it, why ????  Unless you are doing it for testing purposes for the developer, just don’t use…

Edited February 5, 2023 by Stuart1971

[StuartT]

thanks so much everyone. I have a guide rate of 0.8 set, but I'll drop it to 0.5 and do a new calibration and see if that fixes my issue.

[StuartT]

ok, having reduced guide rate to 0.5x in both RA and Dec I had to create a new profile. Seems to be working now. Thanks everyone!

 

Edited February 5, 2023 by StuartT

[Stuart1971]

24 minutes ago, StuartT said:

ok, having reduced guide rate to 0.5x in both RA and Dec I had to create a new profile. Seems to be working now. Thanks everyone!

 

Yes, that should work much better, I had mine on 0.9x for a while and it was all over the place…when I reduced to 0.5x it was far better….👍🏻