M27 in a Canon 60Da

Here is a summer time project made up of data from three imaging sessions. A friend challenged me to see if I could bring out the very faint outer halo without using filters. It took over three hours of exposure in total, but the halo is there. Click on the image to see a higher resolution view. Click again to return to the original.

Object	M27, RA 19:59.6 Dec 22:43
Exposure	209 minutes (69 X 3 minutes)
ISO	1600
Camera	Canon 60Da DSLR
Optics	200mm SkyWatcher f/5 Newtonian reflector with Paracorr for a total focal length of 1150 mm
Location	Marion Bridge, N.S., St. Croix, N.S. and Smiley's Provincial Park
Processing	Calibration and stacking Images Plus . Masked stretching and split star processed in Images Plus. The masked stretch limits the increase in noise when stretching the image. After the initial stretch the feature mask was used to split the stars from the image and SMI processing was used to further enhance the nebula. Colour enhancement done in LAB colour space using Images Plus 6 beta with curves. The star colour was enhanced by selectively increasing the red then the blue saturation. Finally the two images were recombined and the background brightness was set using levels to adjust the black point.