Object: The Horsehead Nebula - Barnard 33
Date/Time: H-alpha data - 12/15/06, RGB data - 12/16/06
Location:  My backyard, Las Cruces, NM.
Camera: Meade DSI Pro II using Schuler 9mm Ha and Meade RGB filters
Exposure: HaRGB 72:30:30:30 @ 4:2:2:2 minute subs 
Telescope: TeleVue 85mm refractor (f/5.6) on a Meade LXD75 Mount
Guiding: Modified webcam and GuideDog SW
Processing: Calibration, registration, stacking, and Ha+R,G,B combination using ImagesPlus and PhotoShop. Noise reduction using SBNR2. The image had a bad gradient in the lower left corner due to stray light from the bright star Zeta Orionis, just out of the field of view.  I struggled with it for a couple of days but was finally able to remove most of it.
Comments: This region of beautiful nebulae is located in the constellation of Orion surrounding the left-most star of the belt. The Horsehead is a dark absorption nebula blocking the light from a dim red emission region behind it.  You can view the H-alpha data for the image here. 

© Dave Dockery 2006