M27 - The Dumbbell in OIII

20:37 9/8/2009 UTC

I continued to fine tune the system with M27 using OIII filter. I am getting pretty sharp results already, but there's a small elognation in RA left probably due to the spur gears between motors and worm gear. The gears are causing a high frequency periodic error which is hard to guide out. Moon was high up and eventually clouds interrupted my session. This image is a 100% center crop of the full 2k x 2k pixel frame.

Camera: Atik Instruments 4000LE | Telescope: Skywatcher ED80 Pro 80mm f7.5 refractor, William Optics 0.8x focal reducer | Mount: Vixen GP-D2, Boxdoerfer PowerFlex MTS-3SLP drive controller | Filters: Baader OIII 8.5nm 2" | Guiding: , The Imaging Source DMK 21AU04.AS CCD camera, Orion ShortTube 80mm f5 refractor, Stark-Labs PHD Guiding | Exposure: OIII 4x600s (40m) unbinned CCD @ -10° f6 | Software: CCDWare CCDStack, Adobe Photoshop CS4, Stark-Labs Nebulosity 2 | Location: 60°31'N 26°52'E (Koivula/Kotka,FI)