SaratogaSkies Jim Solomon's Astropics

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M13 (Great Cluster in Hercules)   [obsolete]

Click to see high-res version.

Image Details:

Camera: Mofidied Canon Digital Rebel (300D): Hutech (no filter)
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: 30 x 1min @ ISO 1600
Total Exposure: 0hrs, 30min
Date: 6/4/2005 10:34:53 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

Processing:

  • IRIS: Dark subtraction, Flat field, Best frame selection, Registration, Gradient removal
  • JimP: Kappa-Sigma stacking, White balance, ASINH stretching
  • Photoshop: Levels, cropping, JPG conversion

Image Description:

This is the Great Cluster in Hercules, aka M13, a showcase globular cluster for stargazers in the Northern Hemishpere. This was taken on the same night and with the same lousy conditions as this M57 image. See that writeup for more details on the conditions and the processing.

For this image, I used fellow Saratogan Rich S.'s modified 300D (Thanks Rich!), though the modified camera probably didn't make much of a difference with this particular object. Check out my previous attempt at M13 for a comparison. This is the full frame, shrunk for display on the web. The full-resolution image is also available. North is up.

 
NGC 7331 (Deer Lick Group and Stephan's Quintet)
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 7331 (Deer Lick Group and Stephan's Quintet)

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

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: 15 x 8min @ ISO 400
Total Exposure: 2hrs, 0min
Date: 9/22/2004, ~12:40am 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

Processing:

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

Image Description:

This is a rich field of galaxies in the constellation of Pegasus. The two major groupings are the Deer Lick Group, in the upper-left, and Stephan's Quintet in the lower-right. NGC 7331 is the largest and most obvious galaxy in this picture, and is the "showcase piece" in the Deer Lick Group. The tracking seemed a bit better in the frames of this image versus previous ones, perhaps due to the insertion of the barlow lens in the guide scope, doubling its effective focal length. This is a composite crop of both galaxy groups at roughly 75% size. A full-resolution image is also available. North is up.