My backlash settings behave differently before and after alignment. Is there a problem with my mount?
April 1, 2010
If you adjust your mount’s anti-backlash settings before it's aligned, it is either not tracking or tracking in a different direction when aligned on the sky. This puts different demands on the motors and encoders to accurately point the mount during GoTo commands and different demands on the feedback loops involved in anti-backlash and the need to resume tracking right after a GoTo.
When the mount is aligned on the sky, it is tracking only in RA for a properly aligned equatorial mount. Even with an Alt-Az mount like the SE or CPC models, most of the tracking motion is west because of the sky’s apparent motion.
Therefore, you should expect both the mount’s anti-backlash settings and its actual anti-backlash motions to different before and after alignment.
In general, it’s best to adjust anti-backlash settings under the same conditions of tracking, mounting the scope on or off a wedge, and with a load you are actually going to use for the best performance.