Witch Head Nebula - IC 2118

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The Witch Head nebula, in Orion, is a well known subject also for Northern Hemisphere photographers thanks to the not so negative declination (-8°). But from my home at +46°N the maximum altitude on the horizon is 36°, while in Tivoli Farm (lat 23°S) the max alt is 75°! Then add the perfect sky (22 mag/arcsec^2) and the absence of humidity (27%), and the result is much better respect a longer exposure I've made with exactly the same instrument from Italy. See here for comparison.

Technical data
Optics Pentax 75 apo refractor
Focal Length 500 mm
Focal Ratio f/6.7
Exposure Time 1 h 40 min (single exp of 10 min)
CCD Canon EOS 5D with Baader filter
Sensitivity 800 ISO
Location Tivoli Farm (Namibia) at 1350 m height
2 September 2011
Mount Kenko NES
Tracking Lodestar with a small refractor (F.L. 100 mm, aperture 23 mm)
Temperature and humidity T= +7°C, RH=27%
Sky brightness at zenith (with SQM-L) 22.0 mag/arcsec^2
Notes This image is a collaborative effort of the Namibia 2011 expedition. Processing: Lorenzo Comolli. Images by: Lorenzo Comolli, Luigi Fontana, Giosuè Ghioldi, Emmanuele Sordini.

HTML Editing and Publishing by Lorenzo Comolli. Email me at comolli@libero.it.
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