SaratogaSkies Jim Solomon's Astropics


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IC 405 (Flaming Star Nebula)

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Image Details:

Camera: Mofidied Canon Rebel XT (350D): Hutech Type I Filter Replacement
Mount: Celestron AS-GT
Scope: Celestron C8-N (8" f/5 Newtonian)
Configuration: Prime Focus
Additional Optics: Celestron/Baader Multi Purpose Coma Corrector (MPCC)
Filter: None
Effective Focal Length: 1000mm
Effective Focal Ratio: f/5
Exposure: 38 x 4min @ ISO 400
Total Exposure: 2hrs, 32min
Date: 1/4/2006 10:44:54 PM PST (start)
Location: Saratoga, CA, USA
Acquisition: DSLRfocus
Focus: DSLRFocus
Dithering: GADFly 1.0.5
Guiding: GuideDog via Philips ToUcam Pro II (840k) through Orion ST80 w/ Celestron 2x "Kit" Barlow


  • IRIS: Dark subtraction, registration, gradient removal
  • JimP: Flat field, Kappa-Sigma Stacking, White balance, ASINH stretching
  • Photoshop: Levels, cropping, JPG conversion

Image Description:

This is IC 405, aka the Flaming Star Nebula, in the constellation of Auriga. This was shot on a night of absolutely horrible transparency. To see how bad it was, check out this animation, which shows each of the 38 exposure played back-to-back as a movie. Notice how many of the shots were wiped out by clouds. Surprisingly, stacking all 38 of the images produced a better result than selecting the best images and stacking only them. Perhaps the Kappa-Sigma operation is automatically rejecting "bad" data. A higher-resolution image is also available. North is up.