Any use for a wedge on a GPS scope?

Hi:
I have a 12" Meade Lx200 GPS and have been able to take upto 90 sec exposures with a CCD unguided. I was thinking of buying a wedge for better polar alignment. Is this a good idea or will I not be able to take longer unguided exposures with the wedge. Is ther a real value to the wedge? Please help
kindest regards
ashton

You can't really be polar aligned at all on the LX200. I can't imagine how you're able to take 90 sec shots on that system (in its stock configuration) without experiencing field rotation - I would assume 30 seconds was the best you could do and 60 seconds would really be pushing it. You could get a field de-rotator to counter this, or you could get a wedge and turn your mount into an equatorial one in which case field rotation would no longer occur. Of course you could still experience tracking errors depending on how well you align and how well your mount tracks.

With a perfectly aligned equatorial mount of ideal mechanical quality and tracking rate you could theoretically shoot unguided shots indefinitely. I don't think there's a lot of mounts like that out there