At Rancho Hidalgo, I set up the Canon with my standard 28-135 zoom and the tracker head. The tracker has a small polar scope, and the alignment just uses that. I shot constellation scale tests, mostly at 28mm with ASA from 1600 to 6400. Here’s a 3 minute exposure of the Scorpius region at 6400. There’s no calibration. I adjusted levels and curves in Photoshop. There’s more noise in the image than you would want, but I found that ASA 3200 was acceptable assuming use of dark and bias frame sets and stacking multiple frames to reduce noise. The greenish crap on the lower third is due to smokey haze from Arizona wildfires. See https://www.jjmcclintock.com/?p=139.
