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Starcrazzy
26-03-2006, 07:31 PM
Hi guys...Here's my second go at the dsi...finally got decent skies, but still a little dissapointed..I have spent hours and hours drift alligning my mount (eq5) but i can't for the life of me get the last bit of drift out...it shows no drift up or down on both axi but gets drift in RA after only 20 seconds...ggrrrlll...im ready to pull my hair out...has anyone got one of those eq5's from andrewws??anyway..tell me what you think...its a composite of 8 composites(if ya know what i mean...) i let the dsi stack 10 or so 14 second exposures and save the final image and then repeat the process and stack 8 of the final images in registax...i am obviously let down by this darn drifting....
ps...quite happy with the diffraction spikes..:thumbsup: :thumbsup:

[1ponders]
26-03-2006, 07:39 PM
You will always get drift in RA SC. It's called periodic error and to remove it from your images you need to guide your scope. It comes from inaccuracies in your worm gear and RA gear. If you do a google for Periodic Error (PE) you will find heaps of stuff. You'll find heaps searching here.

In a short focal length scope like an Orion ED80 at 600mm you might be able to get away with short unguided shots, but your focal length would be double that wouldn't it? therefore guiding errors show up much sooner.

EzyStyles
26-03-2006, 07:53 PM
Nice shot of ETA Starcrazzy. You're getting there :)

I suggest don't let it stack automatically but save the frames individually and stack em in registax. That way, you will notice less drift.

keep it up ;)

Starcrazzy
26-03-2006, 08:01 PM
Thanx ezy and ponders...i have a 80 mm short tube refractor which i can attache to the scope, but, in order to guide does it need to be perfectly alligned with the main scope ie. crosshairs on the same object im imaging or can it be off to one side slightly??