Monday, January 09, 2012
Comet C/2009 P1 Garradd - G20, G14 January 5, 2012
Comet C/2009 P1 Garrad taken with the iTelescope T20 colour instrument and the T14 instrument in Mayhill New Mexico on 5 January. I took 3 x 300 second images for T20,and 5 x 120 second images for the T14 instrument. Left: T14 Images stretched individually in FITS Liberator with Arcsinh (Arcsinh x) and auto scaling. Stretched images then stacked on the comet using ImageJ, and the stack Summed using Z project. After that I did a square root process to clean up the background a bit. Top Right: T20 Images converted to RBG using ImageJ, stacked on the comet and the stack Summed using Z project. Click on images to embigen (you will need to to see the ion tail details, especially in colour.
The B&W T14 image stack turned out very nicely, with the ion tail clearly defined. The T20 colour image is muddy and shows poor detail (image cropped and rotated to matche the orientaion of the T14 instrument). I'm obviously doing SOMETHING wrong in processing, the JPEG preview thumbnails show the ion tail more clearly.