SaratogaSkies Jim Solomon's Astropics

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IC 1287 (Reflection Nebula)

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: 10 x 4min @ ISO 200
Total Exposure: 0hrs, 40min
Date: 8/4/2004, ~11:40 PDT
Location: Saratoga, CA, USA
Acquisition: DSLRfocus
Focus: DSLRFocus
Dithering: None
Guiding: GuideDog via Philips ToUcam Pro II (840k) through Orion ST80 w/ Celestron 2x "Kit" Barlow

Processing:

  • IRIS: Dark subtraction, flat frame, registration, Kappa-Sigma stacking, and noise reduction
  • Photoshop: Color mixing, cropping, image scale, JPG conversion

Image Description:

IC 1287 is a very faint reflection nebula in Scutum. This is my second guided image. Thanks much to Jim Shuder for bringing his guiding apparatus over to my house for a fun evening of imaging. (See the comments in the B86 Image for details on the guiding infrastructure.) This is approximately 2/3's of the full frame, scaled for display on the web. North is up.

It's interesting to compare this version with my original unguided version. This one shows much tighter stars and much more of the faint, blue nebulosity. Now, to be fair, the guided version has twice the effective exposure length as the unguided version. But that was because nearly 2/3's of the unguided exposures were unuseable messes, due to smearing and poor tracking. Seen another way, in the unguided version I collected 60min of frames, of which only 20min were useable. In the guided version, Jim and I collected 40min of frames, of which all were useable. Bottom line: I'm convinced; I need to begin guiding.

 
M109 (Barred Spiral Galaxy)
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:

M109 (Barred Spiral Galaxy)

[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: 42 x 4min @ ISO 400 (RGB), 24 x 16min @ ISO 1600 (Hα)
Total Exposure: 9hrs, 12min
Date: 5/16/2006 and 5/17/2006
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, Hα Combination, White balance, ASINH stretching
  • Photoshop: Sharpening, Levels, cropping, JPG conversion
  • Neat Image: Noise reduction

Image Description:

This is M109, a Barred Spiral Galaxy in the constellation of Ursa Major. This is also First Light for my new Hutech Hα Front Filter (HA-FF). For this image, I captured 6.4 hours of Hα over two nights, and 2.8 hours of RGB data on a third night. Not sure it was worth it. .

The Hα regions, such that they are, appear as the small, cherry-red regions in the spiral arms of the galaxy (see the full-resolution image). M109 turned out to be a poor choice of target for testing the Hα filter. This is because the Hα regions in M109 are very small; i.e., not easily resolved, even at the reasonably long focal length of my Newtonian (1000mm). Of course, using a DSLR doesn't help, since the Bayer matrix permits only one in every four sensor locations to record the Hα wavelength. M101 and M51 are in my cross-hairs while I wait for the summer Milky Way objects to be well placed at my site (namely, West of the Meridian early at night).

The image above is a slight crop of the full field. A full-resolution image is also available. North is up.