Why does my hand control show the message “There are no objects available in the alignment zone at this time?”
November 10, 2011
Celestron’s NexStar hand control firmware uses both slew limits and filter limits to select observable objects among all objects in its database. These functions give lists of objects for alignment and observing purposes. They can be set depending on your mount and your observing location to only present objects that your scope can move to for observation without interference from either the mount or a high horizon.
If the slew-filter limits are set too low or to unusual values that exclude much of the visible sky, you may see the message, "There are no objects available in the alignment zone at this time. Press undo and select a new alignment type.” To clear it, either reset the hand control to factory defaults (Menu > Utilities > Factory Settings) or go into Scope Setup and change the Slew Limits and Filter Limits settings.
Most of the time the lower limit for both should be set at zero degrees unless you have a really high horizon (mountains, trees, etc). The upper limit depends on mount type and usually should be set at angles between 65 and 90 degrees.