SaratogaSkies Jim Solomon's Astropics


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NGC 2392 (Clown Face/Eskimo Nebula)

Image Details:

Camera: Canon Digital Rebel (300D)
Mount: Celestron AS-GT
Scope: Celestron C8-N (8" f/5 Newtonian)
Configuration: Negative Projection (Barlowed)
Additional Optics: TeleVue 2x Barlow
Filter: None
Effective Focal Length: 2250mm
Effective Focal Ratio: f/11.1
Exposure: 20 x 5min @ ISO 200
Total Exposure: 1hrs, 40min
Date: 3/14/2005 8:45:52 PM PST (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, flat field, registration, Kappa-Sigma stacking, Richardson-Lucy deconvolution
  • JimP: White balance, ASINH stretching
  • Photoshop: Compositing, levels, cropping, JPG conversion

Image Description:

This is NGC 2392, a Planetary Nebula in the constellation of Gemini. It is also known as the Clown Face and Eskimo Nebula, for fairly obvious reasons.

I was dissapointed at first with this one, since a straight stack in IRIS provided very poor detail in the nebula region. However, 20 iterations of Richardson-Lucy deconvolution really brought out the detail nicely, particularly in the "fur" region. Unfortunately, though, R-L made the stars look, well, icky, so I composited the deconvolved nebula with a straight stack for the star background in Photoshop. Yes, that's cheating. No, I don't care.

Great care was taken during the aquisition and processing of this image so as not to clip any of the detail in the nebula, including the central star, in order to preserve the colors. This is a crop of the full-size frame. North is up.