🔭 Telescope Mount: Worm Periodic Error, Star Trails and Autoguiding (2D)

Image of three stars in a long exposure through a telescope on an equatorial mount whose worm gear is not perfect. Set the number of teeth on the worm wheel, the periodic error, a steady rate error, the exposure time, the focal length, the pixel size, the seeing and the settings of an autoguider, and see the length of the star trails in arcseconds and pixels, whether the stars stay round, and how the guiding loop reduces the error. The worm period, the worst trail, the guiding loop and the image scale are checked with four in-page numerical checks.

2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install