Horsehead NGC6781 Horsehead

(Click on image for Full Resolution)

Date: July 25, 2005
Exposure: RGB : 60:100:90
6 x 600s R , 10 x 600s G & 9 x 600 B
Processing: CCDAutoPilot2 in control for all images - CCDSoftV5 for image acquisition. MaxIm for image calibration,(5 each RGB flats, dark subtracted and median combined, 20 bias frames median combined, 8-600s darks Sigma Reject combined), alignment, normalization, stretch, and RGB combine. 1 iterations of CCDSharp on the Blue layer. Photoshop CS for RGB processing,final adjustment and jpg conversion.
Conditions: Clear, good seeing, high humidity and heat
Scope: RCOS 16" Truss @ f/6
Camera: ST-10XME/CFW-8A -10°
Comments: This is my "First Light" image with the RCOS 16". I had to use water cooling to get the camera down to -10C. I let FocusMax run every 30 min. The focus point changed only 16 counts over the entire session. And I learned a valuable lesson.... Don't take dawn sky flats when the humidity is high. The flats for this image were taken with the dew dripping off the front ring directly onto the primary as it pointed up to the optimum position. :-((. I now have a few nice water spots on my mirror.