M31 - The Andromeda Galaxy
Description: M31, the Andromeda Galaxy, in the constellation of Cygnus. This image was taken on July, 2009 from my home in Snohomish, Washington.
This image is the first light test of my new wide field imaging setup. The telescope and mount are my C8 optical tube on my CGE mount. I've had this particular OTA and mount for many years, the C8 dating back to 1998. The new equipment that allows the C8 to produce the very wide field shown is the Hyperstar 3 lens from Starizona and a QHY8PRO camera. The Hyperstar lens replaces the removable secondary mirror on the C8 and attaches to the corrector plate on the front of the telescope. The camera is a 6 megapixel one-shot-color camera made by QHYCCD. This is a variation of their popular QHY8 camera, with the main difference being that the PRO version is cylindrical in shape and about the same diameter as the secondary obstruction on the C8. This means that the camera does not add to the C8's central obstruction.
The conditions were a bit challenging, with a three quarters moon and moderate light pollution. Also, I took 60 subexposures, but could only use 45 of them. At that point in the run, the sky started getting lighter and the later subexposures were throwing the color balance way off until I removed them.
Equipment: The image was taken with an 8" Celestron C8 telescope on a Celestron CGE mount with a Hyperstar 3 lens. The camera was a QHY8PRO. I had an IDAS light pollution filter in the optical train. The exposures were guided with Astro-Tech AT66ED refractor and Meade DSI Pro piggyback mounted on the C8, using PHD guiding software. Focus was done manually through a Feature Touch SCT focuser on the C8..
Exposures: 45x120 seconds binned 1x1.
Processing: Image capture was done with Maxim/DL 4. Calibration, registration, noise reduction and stacking were done in CCDStack. Curves, levels and zone processing were done in Photoshop CS2. Gradient processing was done with GradientXTerminator.
Click on image for full resolution.