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Old 22-12-2008, 05:11 PM
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AlexN
Tunnel Vision

AlexN is offline
 
Join Date: Mar 2008
Location: Brisbane, Australia
Posts: 6,708
I used the polar scope in my Eq6 ONCE!.

Mind you, the alignment was good... I was planetary imaging at 6.2~6.5m focal lenght, and holding jupiter in the tiny tiny field of view for 35~40 minutes without my input.... however if I plan on imaging deep sky, even with guiding I drift align. Unless you're using a TOP TOP quality mount, the polar scope is not going to be accurate enough to get the scope properly aligned. The Takahashi mounts seem to have perfect polar scopes in them, as do the Astrophysics mounts (from what I've been told)

I've taken to drift aligning in a big way... Before I did it, i could do 30 second exposures before drift ruined images... After drift aligning, I was able to run 4 minute exposures without guiding with nice round stars...

Even WITH guiding, your results are always better if your polar alignment is perfect, and with any of the cheap, mass produced mounts, the polar scope is not adequate enough... Drift alignment is easy, and a skill everyone with a GEM hoping to do photography should learn...

Alex.
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