First, I did some recabling to move the NUC off the scope. I connected all devices to the USB hub - except the FLI camera. Then I connected to the USB hub and the FLI camera to the USB outlets in the versaplate
<image of versaplate with USB cables>
And then just one USB cable from the scope to the NUC.
<image of NUC connected to scope>
After some setup, I first tried to figure out what is happening with the "center" command in SGPro. Checking the log file, I found the following exception:
Turns out that the "Inhibit..." setting in the Paramount Ascom driver returns an exception when SGPro tries a sync after a Plate Solve. I checked if it's possible to turn that off, but couldn't find anything. I searched the SGPro forum and found a relevant discussion <link> and also a discussion in the Bisque forum <link>. Seems to be an incompatibility between TPoint/TSX and SGPro. I asked on the SGPro forum if it would be possible to add a setting that would avoid the sync after a Plate Solve and Jared replied that this should be fixed in the next version (where they will check if a mount can by sync'ed before issuing sync commands - yei!)
Next, I tried to figure out what was wrong with my plate solves in TSX. Earlier that day I talked to a friend who is using TSX and Paramounts for some time. He said that he can get very reliable plate solves with binning 4x4 and 5 sec exposures. And he is using the Red filter to allow him to plate solve even when it's not fully dark. I tried that (had to remember to set the scale to 4.88 arcsec/pixel because I'm binning 4x4!), but still had only a 20% success rate. In then did two model runs to improve my polar alignment, but that didn't help. Played with several ImageLink parameters - still no luck. Finally, I compared with SGPro. I loaded an image from TSX into SGPro and tried to plate solve - didn't work! Then I loaded an image that I could plate solve in SGPro into TSX - and it worked!!! So, it was the image capture itself.
... and finally when I compared the images directly I noticed that the TSX image was MUCH smaller. And when I looked in TSX's camera settings the "Subframes" checkbox was checked!!! AAAAHHHHHH!!! I unchecked it, took one image - and voila! Plate solved!
But now it was 3am and I need to go to bed.