Help PHD2 is calibrating in only 2 steps

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Shaan Ahmed

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Oct 10, 2019, 8:48:59 AM10/10/19
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Hi,

 

I'm sure I must be doing something simple quite wrong, but I can't seem to figure out what the problem is.

The problem is that when running a calibration routine with PHD2 it finishes after completing just 2 steps East, west, north and south. Instead of taking the recommended 12. What this means is that I can't guide at all using PHD2, which is really stopping me from taking long exposures. 

 

To date I have tried reinstalling PHD2, following most of the best practice guide, I have changed the RA side reel rate in EQASCOM regardless of whether I use 0.1 or 0.9 it always does a 2 step calibration and even went as far as reinstalling windows completely. Nothing has worked. 

 

When calibrating I try and keep the DEC to around 20 or below, its hard where I live to get to 0, furthermore I am polar aligning fine using sharpcap so PA is usually rated good or excellent depending on my patience. 

 

Here are some screenshots to show what I have going on in the settings. 








Eqmod Ascom Setup.PNGPHD2 advanced setup.PNG


Detailed calibration parametres.PNG

Also, I have attached some log files from last night. They don't show much but do show that its calibrating in 2 steps. 
Equipment wise:
 
EQ6-Pro mount
ZWO 120 mm guide cam 
Evoguide 50 ED guide scope
 
Thanks,

PHD2_GuideLog_2019-10-09_231849.txt

Bruce Waddington

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Oct 10, 2019, 11:36:12 AM10/10/19
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Hi Saan, I’m sorry you’re having all this trouble.  But this is really a mess, it looks to me like the mount isn’t behaving correctly at all – it certainly isn’t a PHD2 issue.  To start, the pointing info indicates you’re doing calibrations at an hour angle of -7.3 hours, which would mean you’re probably pointing below the horizon.  I really doubt that was the case – roughly where was the scope pointing relative to the east or west horizon?  Is it possible the mount hasn’t been correctly initialized?  Next, you have very different guide speed settings for RA and Dec.  Perhaps in your experiments with the guide speed, you were changing only the RA axis.  That’s not a good idea.  I think you should go back to the very basics at this point:

 

1.        Make sure the mount is correctly initialized and knows where it’s pointing.  Point the telescope at your typical Dec=20 position and within 10 degrees of the celestial meridian – you want the scope pointing at least 60 degrees above the east or west horizon.

2.       Make sure it’s tracking at the sidereal rate

3.       Re-apply all the EQASCOM settings discussed in this document:  https://github.com/OpenPHDGuiding/phd2/wiki/EQASCOM-Settings.  Having taken this scorched Earth approach to trouble-shooting, you will now have to manually check every single setting in every single app  – you can’t assume that anything you set in the past will still have the correct value.

4.       Set the EQASCOM guide speed settings to the same values for both axes – try 0.75x for now.

5.       Connect to the mount with PHD2 and start looping with 2-sec exposures.  Use the Manual Guide tool in PHD2 to move the mount in all 4 directions sequentially.  Use a manual pulse size of 1200 or 1500ms and issue 7-10 pulses sequentially in each direction.  Watch the PHD2 image display and see if the stars in the field move in all 4 directions.  In your calibrations, the movement was apparently only in one axis.

6.       If you can see the stars moving in all 4 directions, let PHD2 try to do a calibration.

 

If you can’t get through these steps successfully, you will probably have to discuss the problem on an EQ-specific forum or with the mount vendor.  FWIW, I wish you had asked about this when you first saw the problem so we could have advised you to not start tearing apart the software configuration on your computer.  At this point, once the mount is working correctly, it may take you some time and effort to get everything put back together.

 

Good luck,

Bruce

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Shaan Ahmed

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Oct 10, 2019, 1:14:51 PM10/10/19
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Hi,

Thanks for getting back to me.  I am going to install all the programs and software on a different laptop and see if that helps. At the same time I will try to implement your suggestions on the original laptop and see if I there is any progress.

A couple of questions first based of the back of your feedback.

I had realised part way through launching PHD2 that the date and time was way off on my laptop and consequently changed it in the windows settings. Could that have led to the hour angle of -7.3 hours?

When you say make sure the mount is initialized do you mean that it is parked in home and knows what the home position is? 

How do I make sure its tracking at sidereal rate and what does this mean?

Thanks for your input, whilst we don't have the exact answer yet I feel like we are on the right track. 

Best,

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Andy Galasso

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Oct 10, 2019, 3:37:58 PM10/10/19
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On Thu, Oct 10, 2019 at 1:14 PM Shaan Ahmed wrote:
I had realised part way through launching PHD2 that the date and time was way off on my laptop and consequently changed it in the windows settings. Could that have led to the hour angle of -7.3 hours?

yes, that could explain it.
 

When you say make sure the mount is initialized do you mean that it is parked in home and knows what the home position is? 

If the mount is tracking and capable of go-to commands from your planetarium then it is initialized.   Often mounts require some sort of setup procedure after they are powered on such as aligning on one or more stars so that they have some awareness of how they are oriented.  You want to make sure the mount is initialized in that sense before doing anything with phd2.
 

How do I make sure its tracking at sidereal rate and what does this mean?

often mounts provide different tracking speed settings such as Lunar rate, King rate, or Sidereal rate.  You want to select sidereal rate for imaging and guiding. It's probably there somewhere in the EQMOD settings. Sidereal rate would be the default, but you should confirm that it is set to sidereal.

Andy

Shaan Ahmed

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Oct 10, 2019, 8:39:56 PM10/10/19
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Cali data.PNG

Recalibrated with a new laptop. I think this looks better. What do you think?

Bruce Waddington

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Oct 10, 2019, 9:53:50 PM10/10/19
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Yes, that calibration looks fine to me.   Generally, if you don’t see an alert message in calibration, you should be good to go.

 

Good luck,

Bruce

 

From: open-phd...@googlegroups.com [mailto:open-phd...@googlegroups.com] On Behalf Of Shaan Ahmed


Sent: Thursday, October 10, 2019 5:40 PM
To: Open PHD Guiding <open-phd...@googlegroups.com>

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