Object: The Crab Nebula - M1
Date/Time: H-alpha data - 12/17/06, RGB data - 12/18/06, First Quarter Moon
Location:  My backyard, Las Cruces, NM.
Camera: Meade DSI Pro II using Schuler 9mm Ha and Astronomik RGB filters
Exposure: HaRGB 60:32:32:32 using 4 minute subs 
Telescope: Meade SN6 f/5 reflector on a Losmandy G11 Mount
Guiding: Meade DSI-C and PHD Guiding SW on a 600mm refractor mounted side by side
Processing: Subs registered and stacked (SigmaClip) in ImagesPlus.  Ha combined with Red channel in PS (blended 50% in lighten mode) then Ha+R,G,B channels combined in ImagesPlus.  Levels, curves, and sharpening in PhotoShop.  Background gradient removed using the GradientXterminator plug-in. 
Comments: This beautiful object is a supernova remnant in the constellation of Taurus.  It's all that remains of a massive stellar explosion recorded in 1054 AD by Chinese and Arab astronomers.  The exploding star was so bright that it was visible in broad daylight.  The red tendrils surrounding the nebulosity were recorded using the narrowband H-Alpha filter.  Click here to see the image without the H-Alpha data.     

© Dave Dockery 2007