I’ve been using SGP for a short time with good results. I have a C8 with a Hyperstar imaging at F2 and recently changed the setup with a 6.3FR on the same scope. I did the configuration in the Equipment Manager with the correct resolution. The last couple of nights I’ve had the same thing occur. The sequence begins with a slew to target then it takes the image for the plate solve operation. The image that comes up shows very prominent star drag and the Plate Solve 2 will not solve. At that point I aborted the sequence and using the Frame and Focus panel I tried taking a single image. The stars on that image are round. I repeated these steps several times and the result was the same. Significant star drag on the plate solve image but none on the image taken with the Frame and Focus. I’m using an AVX mount so I’m wondering if there is some communication problem with the mount that is doing this. This is the first time I’ve experienced this problem. This is the first time reporting so I hope I’ve gotten the dropbox link correctly. Cheers.
One thing to check: Do you have or need “settle” time defined for your mount?
Platesolve starts taking it’s initial image immediately after slewing to the target, and for some targets (mostly ones at high declination) I had noticed that even on my AP1100 I needed to wait a couple of seconds for the scope to settle before taking the plate solve image, otherwise I would see elongated stars and on one occasion saw platesolve fail as a result.
Thanks for the response Steve. I haven’t looked into the mount menu for that option but don’t recall ever running into a parameter to set a ‘settle time’. I always see the “guider is settling” message when a dither occurs and assumed that the mount was reporting is status. Do you know if there is a way to separate the steps in SGP such that you center on a target and plate solve manually and then just start the capture sequence instead of using the automation. Not my preference but I hate to waste more good imaging nights.
In the Control Panel or Equipment profile view view under the Telescope tab there is a “Mount settling time” field where you enter in seconds how long to wait for the mount to settle before continuing with the next operation.
Do you know if there is a way to separate the steps in SGP such that you center on a target and plate solve manually
You can do this yes. In your Target Settings view:
- Disable the SLEW and CENTER option (just select SLEW or “do nothing” option instead")
- Before running your sequence click the Center Now button to slew, center and plate solve “manually”
If you do meridian flips though this would be a problem as you would really want SGP to re-center and platsolve after a flip.
Again, I’d try adding a settle time to see if that solves your elongated stars issue and then leave centering/platsolving enabled - it really is agreat feature and has been working for me without failing for a long time now.
Thank you Steve,
I looked and ‘discovered’ the settling time in the control panel and upped it from 2s to 10s and will give it another try tonight. I also noticed in the same panel that aperture was set at 2.0 meters instead of 0.2 meters. Don’t know if that made a difference but at least I caught that.
Cheers,
Keith
I found that the blind solver (ANSVR) is better able to solve star trail images than PS2, which in turn was a bit better than ASTAP. The blind solver seems to take for ever but if you are running an unattended imaging session it is useful to have as a backstop to help prevent e.g meridian flips failing.
Thank you Paddyfield, I’ll look into that. Last night was another failure. Well, one thing worked. By increasing the settle time for the mount from 2s to 10s the image showed no signs of star drag and in fact I could see that the target (M33) was even in the frame yet Plate Solve 2 failed. I must be missing something. If anyone can read the logs, here they are.
Dropbox - File Deleted g_logfile_20201218200143.log?dl=0https://www.dropbox.com/s/mwa69egzyx336ix/sg_logfile_20201218203539.log?dl=0https://www.dropbox.com/s/xrhkiomn2g7wj69/sg_logfile_20201219065443.log?dl=0
){kind=link}
Many SGP users have switched from PS2 to ASTAP, I think mainly because ASTAP doesn’t have PS2’s irritating 10 second countdown. You can find instructions on using ASTAP elsewhere in the forum. I’ve had images which ASTAP could solve but PS2 couldn’t, and vice-versa. Use the Plate Solve tab in Control Panel to test plate solving and determine the best choices for exposure length and binning. And of course it is essential that you have set the image scale correctly in the Camera tab.