Help with setting up PHD2 to CGE Pro Mount

[Tim Smith]

Ok. I will freely admit I am lost here.  I have a Celestron 14" SCT with HyperStar on a CGE Pro mount.  I purchased a dovetail bar/ST 80 guide scope/Lodestar X2 and downloaded PHD2 to attempt tracking.  I have watched a few YouTube videos and looked over the manual.  Most is a little over my knowledge base.  I am running from the Lodeestar to the latop and from LodeStar to the Autoguider port on the CGE Pro mount.  I am choosing Starlight Xpress SXV for the camera and On-camera for the mount.  I can create my dark images.  Camera will focus and seems to give a good image.  When I attempt to calibrate things go down hill.

Attached are several of the debug and log files.  I tried using ASCOM generic for the mount which seemed to connect by no luck.

I need to reset everything back to factory resets and start this over with some guidance (no pun intended....)

Thanks for any ideas,   Tim

[Andy Galasso]

Hi Tim,

Sorry you got off to a rocky start with guiding.  I think we will be able to help you get things sorted out.

My first recommendation for you is that you should get rid of the ST4 cable and use an ASCOM connection to the mount for guiding.  If you have not done so already, install the ASCOM Platform, then install the Celestron ASCOM driver.  (More info on the Celestron driver here.)

You are getting bad calibrations (well, you did get one good one), and since you are using an ST4 connection, we do not know if the problem is due to a bad connection to the mount, or for some other reason.  By switching to an ASCOM connection, we will be able to differentiate communication problems from other types of problems. And having an ASCOM connection makes guiding much more convenient since (among other things) you can eliminate the need for additional calibration runs once you do get a good calibration.

Andy

[Tim Smith]

I have verified that I did have the latest ASCOM 6 Platform installed.  From what I read, ASCOM requires a series port on the PC and the series port should run from the PC to which port on the mount?  Autoguider?  I have the StarSense plugged into Aux 1 port.  I think I have a USB to series adapter, but I have never tried it on my newer laptop.

[Tim Smith]

Second question - does it matter that my motor drives on the mount have not had the firmware updated?  This CGE Pro Mount is 9-10 years old.  Tim

[Andy Galasso]

Hi Tim,

I think you will find the answer to your serial connection question in this thread.  If that does not cover it, we'll need one of our Celestron experts to chime in.

Andy

[CyScape]

Do you have the serial cable that goes with the mount? Do you have a usb to serial converter?

[John Stiner]

Tim, the firmware can be updated with the MCUpdate or CFM Manager software available on the Celestron website. Hard to find but I was able to locate with a Google search and updated the firmware a week or two ago. In any event, I'd think the version you have would still support PHD without having to use the "On-Camera" setup (before I updated mine was six years out). Is it not letting you run it through the HC? You might try the Yahoo group.

[John Stiner]

Also, to clarify, and I'm not that familiar with the CGE Pro, but you run your cable from the laptop to the HC, with the HC plugged in to the HC port on the mount rather than the autoguider port.

[Tim Smith]

On Wednesday, January 25, 2017 at 7:01:15 PM UTC-6, John Stiner wrote:

Also, to clarify, and I'm not that familiar with the CGE Pro, but you run your cable from the laptop to the HC, with the HC plugged in to the HC port on the mount rather than the autoguider port.

I found out I have a CGE mount, not the CGE Pro.  I got the communications worked out.  Connected using the USB-to-serial and then into HC to have ASCOM link.  I got it calibrate and did some tracking.  Please take a look at my log files and see if you have in recommendations on how to improve the tracking.  Thanks for the help and setting recommendations.  Tim

[Andy Galasso]

Hi Tim,

I took a look at your log file and I do not see any significant problems. In the first guiding run after your calibration you got about 1.3" RMS error, with RA contributing about 1.1" and about 0.7" from Dec.

Your ~1" RMS RA error is probably about on par for this mount, with PHD2 having most difficulty correcting a ~12 second periodic error.

Your have a fair amount of polar alignment error but this is actually helping your declination guiding since PHD2 is always issuing guide corrections in one direction to counteract the Dec drift. Since The dec motor never reverses direction, you never encounter any Dec backlash.  The only reason this would be a problem would be if you encountered excessive field rotation--primarily a concern imaging near the pole - see this calculator.

At this point I think you are good to go and you can basically ignore your guiding and focus on the other aspects of your imaging.

Enjoy!

Andy

[Tim Smith]

Ok thanks.  Very pleased.  I got so family it was guiding I forgot to ever run the Guide Assistant.  Here are a couple of my images.  They are 15 x 1 minute stacks.

[Tim Smith]

"family" = happy.   I truly don't understand auto-correct some times.   Tim

On Sunday, January 29, 2017 at 8:25:42 PM UTC-6, Andy Galasso wrote:

[Andy Galasso]

Wonderful results, congratulations!