Plate solve failure after flip

Hi, New user and really liking some of the features in SGP.
I am having repeated meridian flip fails over numerous nites and am chipping away, but got stuck now and not sure where to go.
Currently, the flip routinely occurs at the correct time, disengages PHD2 from guiding, executes the flip correctly, then tried to center and plate solve… which fails. SGP goes into recovery mode and eventually aborts.

successful log is here:

and fail log here:

It appears that SGP is sending correct hints to the plate solver ASTAP then local The pixel scale is correct the coordinates are ~ correct, but for some reason both plate solvers fail. I keep thinking it must be image scale, since both fail consistently. But all settings appear correct.
I’d be grateful for help

When we send the coordinates to (local and remove) we scale the image and with it the coordinates. It’s possible that doing so may be causing the scale check to fail here. I’ll have to verify that we’re descaling this but it seems like that may be a likely cause.

Also looks like your 1x1 sampling is around 0.8 arcseconds/pixel? What binning are you using for plate solving? It seems your successful run had a smaller solved pixel scale (around 4 arcsecond/pixel) as opposed to your failed one (around 7 arcsecond/pixel). This leads me to believe maybe you changed your binning for the plate solve between the two runs and it is exacerbating the issue I mentioned above.


Yes 1x1 is 0.8. Should I bin for plate solving? Hadn’t thought of that. I did change fro 2x2 to 1x1 since that was my routine in NINA. No other reason.


One issue I had was that my mount settling time was too low, and occasionally after a flip, the first plate solve image would show movement. I have a Celestron CGEM II mount with the settling time set to 5 seconds (in SGP Telescope control settings). Meridian flips work flawlessly, unless there are clouds or it is very windy.


Thanks. Will add time

In general I would definitely recommend binning for plate solving. 2x2 or 3x3. SGP will automatically scale your sampling to match so just make sure what you enter in the camera tab is always 1x1 scaling.

I hope to look into the potential resizing issues in a couple of days. It looks like it’s the check that’s failing when it fails over to Astrometry.NET.