Lorenzo Comolli's Astronomy HomePage

Click on the image for a high res version.

Cederblad 51 is a part of the large Sh2-264 nebula, nicknamed the "Orion's head". Meissa is at about 2.5° to the South. Three main colors are represented: red of the large H-alpha emission nebula (catalog name: GN 05.30.0), blue of the reflection nebulae (they are the Ced 51) and brown of the dust nebulae (many dark nebulae such as: LDN1574, 1577, 1580, 1581, 1597).
Total exposure is quite short due to veils and do not include a separate H-alpha exposure, so it can be improved much. I keep in the to do list!

Technical Data
Optics	TEC 140
Focal Length	1011 mm
Focal Ratio	f/7.2
Exposure Time	Total 2 h 40 min, LRGB 80:30:20:30 min (single exp of 10 min)
CCD	SBIG STL-11000M @-40°C
Location	Pian dell' Armà (PV, Italian Apennines) at 1350 m height
Date	8 February 2013
Mount	Gemini G-41
Tracking	Lodestar on an 80mm f/5 refractor
Temperature and humidity	T= -12 °C, RH=51%
Sky brightness at zenith (with SQM-L)	21.2 mag/arcsec^2
Notes	South at top (for aestetic reasons).