Comet 17/P Holmes was a non-distinct magnitude 17 dot before October 23rd 2007 then it brightened by a million times to a naked eye fuzz ball at magnitude 2.0 (October 30, 2007). Now it has faded to a dim glow as it continues to travel across the night sky. Here it has a close encounter with the California Nebula.
This photograph is a composition of many short exposures taken from my observatory in Douglas County. Sky conditions during the imaging session were not great with intermittent high level clouds, sky was somewhat light polluted.
Click image for larger picture (1260 x 839, 750kb).
|Lens||Canon Macro 100mm f2.8 @ f2.8|
|Exposure||Stack of 28, 60 second exposures at ISO 800|
|Notes||25°F, 90%rh,Fair to poor transparancy and seeing.|
Calibrated with bias, dark and flat frames.
Initial RAW conversion, registration and stacking in IRIS. Gradient removal using a mask to reduce the light pollution gradient.
Noise reduction in PixInsight LE 1.02 Adjustments in Photoshop CS2