Changes

If your target moves at a non-sidereal rate, specify it here to add orbital elements to enable your target’s coordinates to be determined at the time the observation starts.  Note that if your Instrument Category is set to SPECTRA, this option will automatically activate non-sidereal tracking, but not for imaging.  If your imaging target moves slowly enough (and your exposures are short enough) that you’re happy to have it move across a stationary field, select sidereal, otherwise see this the section for [[#Recipe 4: imaging with non-sidereal tracking|non-sidereal tracking in imaging mode].