Lorenzo Comolli's Astronomy HomePage

Click on the image for a higher res version

This star field is between two famous stars: Alnilam (below) and Mintaka (out of field, above). There stars are respectively the central and right components of the Orion belt. North is toward top-left. The field is very interesting because of many faint nebulae, mainly blue colored. They are really faint and here I've acquired more than 7 hours exposure in a single night.
Here is a list of the main objects:

IC 426 is the brightest, on the left.
IC 423 is similar but a little smaller, visible at the top center.
IC 424 is the smaller blue patch at left of IC 423.
LBN 935: the large blue-pink nebulae at right seems not to have a catalog name, and only a small part seems to be cataloged as LBN 935.
NGC 1990, or Alnilam nebula, is superimposed to the star, and distinguishing from the huge star glare is quite difficult.
PGC 3081033 is a small lenticular galaxy. You can find in this image looking in the middle between the IC 426 nebula and Alnilam.
VdB 48 is the blue patch, mainly out of field, on the left edge.

An interesting paper describing the area is Ogura, Sugitani, "Remnant Molecular Clouds in the Ori OB 1 Association", Publ. Astron. Soc. Aust., 1998, 15, 91-8.

Technical Data
Optics	TEC 140
Focal Length	1011 mm
Focal Ratio	f/7.2
Exposure Time	7h10m (single exp of 10 min)
CCD	Canon EOS 5D with Baader filter
Sensitivity	800 ISO
Location	Bogli (PC, Italian Apennines) at 1350 m height
Date	27-28 December 2011
Mount	Gemini G-41
Tracking	Lodestar on an 80mm f/5 refractor
Temperature and humidity	T= -3°C, RH=70%
Sky brightness at zenith (with SQM-L)	21.3 mag/arcsec^2
Notes	Low noise thanks to a dark sky and cold temperatures.