SaratogaSkies Jim Solomon's Astropics

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B33 (Horsehead Nebula)

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

Image Details:

Camera: SBIG ST-2000XM
Mount: Astro-Physics 1200GTO
Scope: TMB 152/1200 APO Refractor
Configuration: Prime Focus
Additional Optics: n/a (Prime)
Filter: Astrodon SII, Hα, OIII 6nm Filters
Effective Focal Length: 1200mm
Effective Focal Ratio: f/7.9
Exposure: {5 SII, 5 Hα, 5 OIII} × 32min @ -20°C
Total Exposure: 8hrs, 0min
Date: 2/7/2008 8:19 PM PST, 2/8/2008 7:20 PM PST (Start)
Location: Saratoga, CA, USA
Acquisition: CCD Commander
Focus: FocusMax
Dithering: CCD Commander
Guiding: Self Guided

Processing:

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

Image Description:

This is B33, aka, the “Horsehead Nebula”, a dark nebula silhouetted against the bright nebula IC 434 in the constellation of Orion. Compare this closeup with the true color, wide-field, DSLR image, which shows the Horsehead in context with the bright belt star, Alnitak.

Mousing off the image reveals a “Hubble Palette” narrowband image, with R:G:B = SII:Hα:OIII. Mouse-over the image to see the H-alpha only image in grayscale. A higher resolution image is also available. North is left.

 
NGC 884 & NGC 869 (Double Cluster)
SaratogaSkies Jim Solomon's Astropics

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December: Test shots with new scopes/mounts

Dec 21: TMB 80/480 Arrives!

Dec 3: AP1200 Arrives!

Nov 30: TMB 152/1200 Arrives!

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NGC 884 & NGC 869 (Double Cluster)

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: Orion ED80 (80mm f/7.5 APO Refractor)
Configuration: Focal Reduced
Additional Optics: TeleVue #TRF-2008, 0.8x Reducer/Flatener For TV-85 And TV-76
Filter: None
Effective Focal Length: 480mm
Effective Focal Ratio: f/6
Exposure: 13 x 4min @ ISO 400
Total Exposure: 0hrs, 52min
Date: 11/12/2005 11:06:31 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

Processing:

  • 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 NGC 884/869, aka, the Double Cluster in Perseus. This shot was a test of the suitability of the TeleVue 0.8x Focal Reducer/Flatener for use with the Orion ED80 refractor. (Big thanks to Jim Nomura for letting me borrow the TeleVue!) This test was prompted by my disatisfaction with the combination of the ED80 and the Celestron 0.63x reducer which, of course, was never designed to be used with a refractor. (An example of the Celestron can be seen in my latest M31 shot.)

I've added this current shot, and the M31 shot, to my ED80 Reducer Shootout page. Based on this data, the Willam Optics Focal Reducer appears to be the best fit for the ED80. Time to trade in the Celestron. <grin>

Anyway, this shot turned out ok, despite a 91% full moon. And I have very few images of Open Clusters, so I decided to post this one. A higher-resolution image is also available. North is up.

 
NGC 7635 (Bubble Nebula)
SaratogaSkies Jim Solomon's Astropics

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Latest news

December: Test shots with new scopes/mounts

Dec 21: TMB 80/480 Arrives!

Dec 3: AP1200 Arrives!

Nov 30: TMB 152/1200 Arrives!

Links:

NGC 7635 (Bubble Nebula)

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

Image Details:

Camera: SBIG ST-2000XM
Mount: Astro-Physics 1200GTO
Scope: AP Starfire 160EDF APO Refractor
Configuration: Prime Focus
Additional Optics: n/a (Prime)
Filter: Astrodon SII, Hα, OIII 6nm Filters
Effective Focal Length: 1200mm
Effective Focal Ratio: f/7.5
Exposure: {8 Hα, 14 OIII, 16 SII} × 32min @ -15°C
Total Exposure: 20hrs, 16min
Date: 8/9/2008
Location: Saratoga, CA, USA
Acquisition: CCD Commander
Focus: FocusMax
Dithering: CCD Commander
Guiding: Self Guided

Processing:

  • IRIS: Registration
  • JimP: Dark subtraction, Flat field, Kappa-Sigma Stacking, White balance, ASINH stretching
  • Photoshop: JPG conversion
  • CCDStack: Deconvolution

Image Description:

This is NGC 7635, aka, the “Bubble Nebula”, an emission nebula in the constellation of Cassiopeiae. This is the first tricolor narrowband image with my new AP 160 Starfire EDF refractor.

Mousing off the image reveals a “Hubble Palette” narrowband image, with R:G:B = SII:Hα:OIII. Mouse-over the image to see a pseudo-“True Color” image, in which those narrowband emission lines are mapped to their approximate color as seen by human vision. Specifically, the red SII and Hα wavelengths are mapped to red, and the aqua (blue-green) OIII wavelength is mapped to both green and blue. Also, a smidge of Hα is added into blue to simulate the Hβ wavelength.

Even after 8 hours of Sii data and 7 hours of Oiii, the image was still fairly noisy in those channels, so I replaced the luminance with the Hα image and cranked the color saturation a little. This really tamed the noise while preserving the essence of the tricolor image.

A higher resolution image is also available. North is up.

 
NGC 7635 & M52 (Bubble Nebula & Open Cluster)
SaratogaSkies Jim Solomon's Astropics

Search

Latest news

December: Test shots with new scopes/mounts

Dec 21: TMB 80/480 Arrives!

Dec 3: AP1200 Arrives!

Nov 30: TMB 152/1200 Arrives!

Links:

NGC 7635 & M52 (Bubble Nebula & Open Cluster)

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: None
Effective Focal Length: 1000mm
Effective Focal Ratio: f/5
Exposure: 45 x 4min @ ISO 400
Total Exposure: 3hrs, 0min
Date: 12/2/2005 7:34:47 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

Processing:

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

Image Description:

This is NGC 7635, aka the Bubble Nebula, and open cluster M52 in the constellation of Cassiopeia. I used shorter subexposures (4min) at a lower ISO (400) than some previous shots (8min, ISO 800) in order to prevent severe over-saturation of the bright stars in M52. It worked pretty well, at the expense of slightly less detail in the faint regions of the Bubble Nebula. It was nice to get outside and grab this shot, as the weather here has been awful and I was in danger of a complete "shutout" this cycle. A higher-resolution image is also available. North is up.