SaratogaSkies Jim Solomon's Astropics


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IC 1848 (Soul Nebula)

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Image Details:

Camera: Mofidied Canon Rebel XT (350D): Hutech Type I Filter Replacement
Mount: Celestron AS-GT
Scope: Orion ED80 (80mm f/7.5 APO Refractor)
Configuration: Focal Reduced
Additional Optics: William Optics 2" APO 0.8x Reducer/Field Flattener
Filter: None
Effective Focal Length: 480mm
Effective Focal Ratio: f/6
Exposure: 23 x 8min @ ISO 800
Total Exposure: 3hrs, 4min
Date: 12/5/2005 10:06:54 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 1848, aka, the Soul Nebula in the constellation of Cassiopeia. Like others, I think this object's shape is more reminiscent of a fetus, or even of the Star Child in 2001: A Space Odyssey.

This image is "first light" with the William Optics focal reducer, which appears to be the best match for the ED80 as determined by my ED80 Focal Reducer Shootout. I'd say it does a mighty fine job.

This image isn't bad, but could probably use more exposure. It dawned on me only after the fact that 3hrs of f/6 is equivalent to only 2hrs at f/5. Another night perhaps. A higher-resolution image is also available. North is up.