Fork mount - GEM

Celestron SCT's come with fork mounts or German equatorial mounts. Why? Which one is better?

The GEM versions seem to be somewhat cheaper

Why do some very avid amateurs mount their SCT OTA's on large, expensive equatorial mounts? Are these mounts better than top notch fork mounts?

Erlend

The GEM versions are cheaper only because of the specific GEM that is being included with the 8" and 9.25" OTA's - the CG5. It does not have GPS or goto like the Nexstar scopes do.

Avid astronomers would prefer a top notch GEM for two reasons -

1. You can put virtually any scope on them, given the right hardware (and these folks will own a lot of scopes over time).

2. A fork mount without an equatorial wedge will create field rotation in long-exposure astrophotography. Even if the center of the photo is perfectly guided, the stars on the outside will appear to rotate around the middle.

I have an LX10 with a wedge that is great, but if I want to get a 10" OTA the whole setup is no good - with a GEM I would not have that problem, assuming the mount could handle the weight.

Ryan O