clic here for 50% size 1963 x 1315 (738 kB)
About this Image
This wide field image of the Christmas Tree Cluster, also known as NGC 2264, is an open cluster of stars embedded in a diffuse nebula.
It is located in the constellation of Monoceros, the Unicorn.
16" cassegrain in corrected primary focus at f/3
|Camera||SBIG STL-11000M at -30C, internal filter wheel|
|Date||Feb 13 + 28, 2005.|
|Sky Conditions||mag 5 sky, temperature -10 C, Moon up|
Ha = 150 minutes (15 minute sub-exposures),
O-III = 60 min (10 minute subs)
blue = 15 min (5 min subs).(
Image aquisition and color combine in Maxim, image calibration, aligning, DDP in ImagesPlus;
H-alpha 50% as L and 100% as red channel, O-III assigned to green, blue as blue channel. curves, unsharp mask in Photoshop; Noise reduction by Neatimage for dark areas;
north is right;