About this Image
The appearance of the quite faint M76 resembles to some degree that of the Dumbbell Nebula M27.
Most probably, the main body (the bar, or cork) is a bright and slightly elliptical ring we see edge-on,
from only a few degrees off its equatorial plane. This ring seems to expand at about 42 km/sec.
16" cassegrain in secondary focus at f/10
|Camera||SBIG STL-11000M at -30C, internal filter wheel; AO-L|
|Filters||Astronomik Ha + LRGB|
|Date||Dec 07, 2005 and Jan 07, 2007.|
2005: mag 5 sky, seeing unstable, temperature 0 C,
2007: mag 5.5 sky, raw FWHM 1.9" deconvolved to 1.5", temperature 0C,
2005: Ha:R:G:B = 60:60:50:60 min (10 min resp. 30 min sub-exposures) binned 2x2
2007: L:Ha = 180:120 min (20 min resp. 60 min sub-exposures) 1x1 bin
Image aquisition, registration and color combine in Maxim;
synthetic luminance from RGB, H-alpha blended into red channel, curves, unsharp mask, color balance in Photoshop; Noise reduction by Neatimage for dark areas;
2007: L incorporated, Ha as red and L; wavelet filtering for bright parts; color balance in Photoshop CS2,