Plate solve aborting the sequence

I am currently working on a mosaic and I am getting intermittent issues with the plate solving. This has happened twice in two nights now where the plate solve fails to work.

I have attached the SGP log (00:53 it starts to go wrong) and also the PHD log. Here you can see that the issue is not cloud related and neither is the target in the wrong place as it is high in the sky. As it’s a mosaic, it’s also only a small distance from the previous frame.

Last time it failed, the Plate solve coordinates were checked and they did indeed relate to the correct patch of the sky.

Can anyone shed any light on what may be happening here?

Both the primary plate solver and the local failed to solve. The primary reported too few catalog stars (whatever that means), times out.

It will be worth seeing if the plate solve image is available and having a look to see if there is a problem with it. The log file gives a few possible locations.


As far as I can see Chris the Plate solve image isn’t saved - But I am happy to be proved wrong,

The log gives a series of paths to the files,

[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Capture complete, attempting to plate solve image C:\Users\Sara\AppData\Local\SequenceGenerator\Temp\

[13/01/2016 00:46:24] [DEBUG] [Telescope Thread] Astrometry.NET convertedAstrometry.fits path: C:\Users\Sara\AppData\Local\SequenceGenerator\Temp\convertedAstometry.fits

They are temporary but may still be around.

If you are not using PlateSolve2 as your primary then change that…once I did this all issues with plate solving went away… just simply did not work for me…

I have never ever had Astrometry.NET fail to plate solve for me. Almost always around 10 seconds. PlateSolve2 works fine but, for me, if the hints are not already fairly close, it fails and Astrometry.NET gets used anyway. PlateSolve2 is very fast if you are close but for me fairly slow if not. Lately I have just been using Astrometry.NET because SGP is not currently working well with my Technical Innovations dome ASCOM driver and does not wait to take plate solve images until the dome has tracked to the scope position, so there is no or a poor image. Not either plate solvers problem, of course.
Are you sure you have downloaded all the required tables for Astrometry.NET for the image resolution you are using?

Cheers guys for your comments. I am using Pinpoint and up until 2 days ago I had zero issues with plate solve - It has only just started and I think that coincides with the updated SGP that I did.

I can confirm that the correct indices for Astrometry.NET are there - As I said, it’s been solving fine until two nights ago

There have been no updates to the centering routine or the PP solver in more than six months so I don’t think that the upgrade to the 2.5 data is doing this. The logs indicate code was executed as expected so there is not much we can do. We can be of more help if you are able to capture the plate solve frame that fails, but right now we get a real message from pinpoint saying it cannot solve the frame. It’s a pretty large scale, are you using the GSC catalog? You might try increasing the exposure length of the integration too (get more stars).

[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Plate Solve Hint RA: 5.60262966099804
[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Plate Solve Hint DEC: 29.02007898356
[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Plate Solve Hint Scale: 6.74510854439094
[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Plate Solve Hint Angle: 1.41820471756634
[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Plate Solve Search: Use up to magnitude 20 stars
[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Plate solve binning: 2x2
[13/01/2016 00:46:23] [DEBUG] [Telescope Thread] Plate solve exp len: 5
[13/01/2016 00:46:24] [DEBUG] [Telescope Thread] Auto center scope frame failed to solve.Solve failed! There are too few catalog stars in the area for reliable matching. Increase the catalog star faint limit, or use a more dense catalog.

Thnks Ken for looking into it. Just as a little more info - I have been using this faultlessly for ages and the issue has happened only 2 nights on the trot. My scope runs at f3.9 and so is certainly fast enough to capture stars, otherwise the previous plate solves in this sequence would have suffered the same issue.

Today SGP was dialled back to the previous version (not beta) and I have been testing a run through of this all evening - I had one plate solve fail where the slewing was still going on when plate solving had started… so I’ve increased the slewing settling time. Apart from that, it worked fine for perhaps as many as 5 run throughs, including parks at the end of the sequence.