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 There are numerous
            objects in Puppis that skim the horizon low on January evenings,
            and this one is one of the very best. Surrounding the loose open
            cluster NGC2467 in the center of this field is the extensive
            emission nebula Sharpless 2-311 which extends over the entire
            1 degree field. Another open cluster that is actually inside
            NGC2467 is to the upper right of center, and is Haffner 18. Seldom
            in the sky do you find two open clusters with one inside the
            other! The small open cluster Haffner 19 and a small round emission
            nebulosity that on some charts is LBN1066 is seen along the top
            of the frame, just left of center. The brightest star in the
            field is SAO174730 at 7.8th magnitude. 

            
Processing notes: As
            is usual for such objects low on the horizon, I had to change
            the color mix ratios slightly to include a bit more blue in the
            mix. Atmospheric extinction reddens low object, and attenuates
            the blue wavelengths. This nebula is much more pink in the center
            than most, and no doubt its higher level of excitation produces
            more green and blue spectral lines in the densest regions.

Instrument:  12.5" f/5 Home made Newtonian
Platform:  Astrophysics 1200 QMD
CCD Camera:  SBIG ST8i NABG with Enhanced Cooling
Guider: SBIG ST4
Exposure:  RGB = 20:20:40 
RGB Combine Ratio:  1: .8: 1.4
Filters:  RGB Tricolor
Location:  Payson, Arizona
Elevation:  5150 ft.
Sky:  Seeing FWHM = 6.0 arcsec (Maxim DL - 10min subframe), Transparency 7/10
Outside Temperature:  5 C
CCD Temperature:  -20 C
Processing Tools:  Maxim DL,  Photoshop, PixInsight
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