Tag: AstroTortilla

Astrotortilla Plate Solving Speed

I’m using Astrotortilla to refine the pointing of the telescope after a goto. It works great but it can be slow as heck. One solve last night took 4 minutes! I made some parameter changes a while ago that improved things but it’s fiddly. One last thing to try is to tell it that my pointing can’t be off by more than so many degrees – i’ll try 15 degrees next time i’m out.

UPDATE: I noticed that the online plate solver at astrometry.net was solving using a different set of indexes 4111.fits for example as opposed to 4211 which i would have. I found and downloaded the 41xx indexes and the difference is night and day – solves are routinely done in 10 seconds! I haven’t needed to change the 180 degree figure to 15.

Guiding Setup

This is not simple, but it is wonderful. I’ve added a small guiding scope(QHY mini) and camera(QHY5L-II-M) to the mount. Sharpcap uses the guide camera for polar alignment; Stellarium will point the mount to my target; AstroTortilla checks that the camera is pointed correctly and adjusts the aim; and PHD2 continuously monitors the image from the guide camera and makes minute corrections to keep the aim perfect.

There are probably limits to how long the guiding setup can hold position but it’s certainly good for 90 seconds even with indifferent polar alignment.