by keithmorris » Thu Dec 11, 2008 4:36 pm
Hi Paull, not a thick question at all. If you don't know something, as, that's how we learn.
A wedge is used on a fork alt/az mount (Meade LX200, LX90 Celestron CPC etc) to turn the alt/az mount into an equatorial one. The wedge goes on top of the tripod/pier and then the fork driven mount goes onto the wedge. The mount is not held level with the ground anymore but at an inclined angle that is equal to your latituge.
Now when you mount moves because the azimuth drive turns the scope is actually moving in Right Ascention to follow stars and other things as they move across the sky.
This is essential for imageing especially long exposure imaging so you don't get star trails.
Keith