SaratogaSkies Jim Solomon's Astropics


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NGC 6820 & NGC 6823 (Emission Nebula & Open Cluster)

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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: 40 x 4min @ ISO 800
Total Exposure: 2hrs, 40min
Date: 8/30/2005 9:41:31 PM PDT (start)
Location: Saratoga, CA, USA
Acquisition: DSLRfocus
Focus: DSLRFocus
Dithering: Manual
Guiding: GuideDog via Philips ToUcam Pro II (840k) through Orion ST80 w/ Celestron 2x "Kit" Barlow


  • IRIS: Dark subtraction, registration
  • JimP: Flat field, Kappa-Sigma Stacking, White balance, ASINH stretching
  • Neat Image: Noise reduction
  • Photoshop: Levels, cropping, JPG conversion

Image Description:

This is a "do over" of NGC 6820, an Emission Nebula in the constellation of Vulpecula. In my previous attempt with an unmodified camera, I was unable to capture the faint Hα emission nebula, and was only able to capture the open cluster NGC 6823. The modified camera excels in shots like this. A high-resolution image is also availble. North is up.