Meade - Ultrawedge

The Meade Ultrawedge for 8/10/12/14-inch LX200 and LX400 Model 07008 telescopes will eliminate field-rotation effects when you're using your telescope for astrophotography.

You can do astrophotography with LX200 and LX400 scopes in the standard altazimuth mode, but with longer exposure times, an effect called field rotation becomes evident. Stars at the edge of the field will appear as small concentric arcs or streaks on the film, rather than as star points. This effect, which does not relate to the accuracy of the telescope's computer or internal alignment, occurs on all altazimuth-mounted telescopes. It's simply a side effect of the altazimuth-type mount itself.