Boy was I impressed with the StellarSolver! Getting the polar alignment sequence shot and solved in 30 seconds? Sign me right the heck up.
Until...it didn't. My initial solves were shot with tree branches and stuff, and the solver worked great. Pointing, capture and slew to target, peerless.
Meridian flip, and then it's as if someone broke the piece marked "Solver" in the box. No better feedback than "Solver failed".
Clear starfield in sharp focus
Parking and starting over didn't help
Parking and power-cycling the Pi and starting over didn't help
Switching some of the options for StellarSolver didn't help
Fortunately my mount's hand controller knows about NGC 281 and got it within the visual field, so I only lost about an hour dinking around. I could try to do logs but I'm not touching anything until the current imaging session finishes.
OK. Not having followed the development, I thought that astrometry and StellarSolver were two different things. Know better now.
One thing I hadn't thought to try previously was a solve off my guide camera. Since moving to an OAG I'd had lots of trouble getting sufficient stars to guide on till I figured out the correct angular position where I could extend the prism enough, so it didn't occur to me. Tried one last night, came back about as fast as my finger left the mouse button (1280x960, no wonder!). After that I uploaded a FITS to nova.astrometry.net so I could get astrometry's idea of my scope/main-camera's FOV exactly right. Hand-entered that, boom, plate solving was back and worked just fine all evening.
Yeah, you could say they are different things, but they aren't as well. Really you could say that I did two things with StellarSolver. 1. I made an internal solver library with an internal build of astrometry.net that requires no external temporary or configuration files. 2. I made a library that can solve using many different methods like using the internal solver library, using ASTAP, using external astrometry.net, and using an online astrometry solver.
So you can say that StellarSolver is astrometry.net, but it is also more than that. I also made a bunch of tweaks and enhancements that can make blind solving blindingly fast compared to before.