Distance 55 mly

Telescope configuration: Celestron EdgeHD 1400 with the Celestron 0.7x focal reducer (fl=2737, f/7.7), unbinned, yielding an image scale of 0.40 arc-seconds/pixel.
Camera: SBIG STF-8300M (monochrome) CCD camera. 2 - 10 minute exposures at -20C and no filter. Image capture using TSXPro/Camera Add-on.
Mount: Software Bisque Paramount MX with PEC and ProTrack enabled. Autoguided with an SBIG Sti autoguider, a Celestron OAG (off-axis guider) and a Starlight Xpress AOLF (Adaptive Optics Large Format) device using PHD2 autoguiding software.
Post processing: Calibration, alignment, stacking in ImagesPlus 6.0 using 9 dark frames, no bias frames and 9 flat frames; DDP and curves in Nebulosity 3.0; Unsharp mask in ThumbsPlus.

20150120_M100_Comb-NEBddpcrvunsmask.tif