SaratogaSkies Jim Solomon's Astropics

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NGC 2903 (Barred Spiral Galaxy)

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: 35 x 5min @ ISO 800
Total Exposure: 2hrs, 55min
Date: 3/30/2005 8:56:31 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

Processing:

  • IRIS: Dark subtraction, flat field, registration, gradient removal
  • JimP: Kappa-Sigma Stacking, White balance, ASINH stretching
  • Photoshop: Levels, image size, cropping, JPG conversion
  • Neat Image: Noise attenuation on galaxy closeup

Image Description:

The large galaxy in the lower right is NGC 2903, a rather photogenic Barred Spiral galaxy in the constellation of Leo. The smaller spiral galaxy in the upper left is NGC 2916. Those with good eyes might be able to pick out PGC 27115, aka UGC 5086, the (very) faint smudge just to the left of NGC 2903. (Hey, it's a dwarf galaxy, and it's Mag 16. ) Also barely visible is PGC 27249 (aka ZWG 122.022), the thin slit just below and left of NGC 2916 (Mag 15.7).

The seeing was pretty good the night this was shot. The transparency was pretty lousy. The image on this page is a slight crop of the full frame, scaled for display on the web. See also the full-resolution image. North is up.

 
M22 (Globular 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:

M22 (Globular Cluster)

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: n/a (Prime)
Filter: None
Effective Focal Length: 1000mm
Effective Focal Ratio: f/5
Exposure: 20 x 1min @ ISO 800
Total Exposure: 0hrs, 20min
Date: 7/14/2004, ~1:30am PDT
Location: Saratoga, CA, USA
Acquisition: DSLRfocus
Focus: DSLRFocus
Dithering: None
Guiding: None

Processing:

  • IRIS: Dark subtraction, flat frame, registration, Kappa-Sigma stacking, background fit
  • Photoshop: Crop (1/2 x), image scale (1/2 x), JPG conversion

Image Description:

This image was taken under some pretty poor conditions: both the transparency and the seeing were pretty bad, and a ton of dew was accumulating on all of the equipment. It's times like these that I'm glad I have a Newtonian reflector, as an SCT would have been eaten alive by the dew. M22 is a larger and brighter globular cluster than M13, although the latter seems to get all of the attention in the Northern Hemisphere. Perhaps it's because M22 is in Sagittarius and therefore doesn't stand out from the Milky Way stars as well as M13 stands out from its background in Hercules. At the eyepiece, M22 is the better sight in my humble opinion. Of course, both of these pale in comparison to Omega Centauri, which is very difficult to view from mid-Northern Latitudes since it is so far south of the Celestial Equator. North is up.