SaratogaSkies Jim Solomon's Astropics

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M33 (Triangulum Galaxy)

Image Details:

Camera: Canon Digital Rebel (300D)
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: 19 x 5min @ ISO 400
Total Exposure: 1hrs, 35min
Date: 11/13/2004, ~10:30pm 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

Processing:

  • IRIS: Dark subtraction, flat field, registration, normalized Kappa-Sigma stacking, background fit, cropping
  • Photoshop: Levels, image size, cropping, JPG conversion

Image Description:

This was the first decent night of weather we've had here in the Bay Area in a long time, so it was nice to get out again and capture this image. The seeing and transparency were good, not great, but far better than they've been in quite some time. M33 is a spiral galaxy, sometimes referred to as the Pinwheel Galaxy, in the constellation of Triangulum -- a constellation which is shaped like ... drum roll please ... a triangle. <grin> This is a crop of the full-size frame. North is to the left.

 
NGC 6960 (Cirrus Nebula)
SaratogaSkies Jim Solomon's Astropics

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December: Test shots with new scopes/mounts

Dec 21: TMB 80/480 Arrives!

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Nov 30: TMB 152/1200 Arrives!

Links:

NGC 6960 (Cirrus Nebula)

[Hα+R G B]

Mouse-over to see annotations. (Requires Javascript) Click to see high-res version.

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: Hutech Hα Front Filter (HA-FF)
Effective Focal Length: 1000mm
Effective Focal Ratio: f/5
Exposure: 30 x 8min @ ISO 400 (RGB), 30 x 8min @ ISO 1600 (Hα)
Total Exposure: 8hrs, 0min
Date: 9/17/2006 (RGB); 9/19/2006 (Hα)
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

Processing:

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

Image Description:

This is NGC 6960, aka the Cirrus/Filamentary/Lace-work Nebula and the Western portion of the Veil Nebula, a supernova remnant in the constellation of Cygnus. This image consists of 4hrs of RGB exposure and 4hrs of Hα exposure over two nights.

Unlike my previous Hα+R G B images, in this one I used Hα for Luminance, and the RGB data for color after first blending a smidgeon of Hα into the Red channel. I suppose that makes this technically an Hα:Hα+R:G:B image. Using Hα for Luminance gives a very high contrast result, with added benefit of attenuating the star field which otherwise tends to overwhelm the rather faint nebula. And blending a bit of Hα into the Red channel prevents the salmon-i-zation (salmonella!? <g>) — i.e., the washout — of the red region that results from simple luminance layering in Photoshop. Robert Gendler has an explanation of this technique at his web site. Mousing-over the image shows the RGB stack, without any of the Hα data. Notice how the Veil tends to get lost in the Milky Way star field in that RGB-only image.

A higher-resolution image is also available. North is left.