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:

• Links
• Help
• About Me

Mars   [obsolete]

Image Details:

Camera: Nikon D100

Mount: Celestron AS-GT

Scope: Celestron C8-N (8" f/5 Newtonian)

Configuration: Eyepiece Projection

Additional Optics: Celestron "Kit" 4mm Plössl

Filter: None

Effective Focal Length: 16000mm

Effective Focal Ratio: f/80

Exposure: 2 x 1/8 sec + 1 x 1/4 sec @ ISO 200

Date: 8/23/2003, 1:30am PDT

Location: Saratoga, CA, USA

Acquisition: Manual

Focus: Manual

Dithering: None

Guiding: None

Processing:

• IRIS: registration, stacking, wavelet processing, cropping
• Photoshop: rotation, image scale (1/2 x), JPG conversion

Image Description:

Taken within days of Mars' historic rendezvous with Earth in August of 2003, within weeks of getting my C8-NGT, and long before I knew what the heck I was doing. It was rather cool of Jon to let me borrow his D100 to get this shot. Mars' North is up.

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:

• Links
• Help
• About Me

Sunset over the Pacific

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

Image Details:

Camera: Canon 5D

Mount: None

Scope: Canon EF 24-105 mm f/4L IS USM lens

Configuration: Prime Focus

Additional Optics: n/a (Prime)

Filter: None

Effective Focal Length: 105mm

Effective Focal Ratio: f/8

Exposure: 1/41.5 sec

Total Exposure: 0hrs, 0min

Date: 5/6/2008 8:13 PM PDT

Location: Russian Ridge Open Space Preserve

Acquisition: Manual

Focus: Auto

Dithering: None

Guiding: None

Processing:

• Canon Digital Professional Pro: CR2 to TIF conversion
• Photoshop: Shadows/Highlights, Levels, Resizing, sRGB color space conversion, JPG Conversion

Image Description:

This is a hurried but nonetheless pleasing shot of the sun setting over the Pacific. This is shot roughly toward Half Moon Bay, which had clearly been socked in by the Marine Layer along with most of the rest of the San Francisco Bay Area. This was one of the first shots I captured before the “main event,” which was this shot of Mercury and the Moon setting together over the Pacific. See the writeup on that image for more information on the location from which this is shot. A higher resolution image is also available. Celestial North is as indicated on the mouse-over. Sunset was at a compass heading of WNW that evening.

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:

• Links
• Help
• About Me

NGC 4725 (Spiral Galaxy)

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: 20 x 8min @ ISO 400

Total Exposure: 2hrs, 40min

Date: 5/16/2007 9:28:57 PM PDT (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: Sharpening, levels, cropping, JPG conversion
• Neat Image: Noise reduction

Image Description:

This is NGC 4725, aka, the “One Armed Galaxy”, a spiral galaxy in the constellation of Coma Berenices. NGC 4725 is a Seyfert Galaxy, suggesting an active galactic nucleus containing a supermassive black hole. A higher resolution image is also available. North is up.

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:

• Links
• Help
• About Me

NGC 6822 (Barnard's 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: 83 x 4min @ ISO 1600 (RGB), 22 x 8min @ ISO 1600 (Hα)

Total Exposure: 8hrs, 28min

Date: 8/23/2006 and 8/24/2006 (RGB); 8/27/2006 (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 6822, aka Barnard's Galaxy, an irregular (as opposed to spiral or elliptical) galaxy in the constellation of Sagittarius. NGC 6822, a member of the Local Group, is a relatively close neighbor of our own Milky Way galaxy, along with M31 (Andromeda) and others.

This image was collected over three nights: two very dewy nights worth of RGB exposures, and a third night of Hα exposures. The Hα exposures really helped to bring out the star-formation regions at the top (North) of NGC 6822. Yes, that's correct, those emission nebulae are in NGC 6822, not in our own Milky Way!

Mousing-over the image will show the Hubble designations of those regions, and will switch the displayed image to the processed Hα-only image, shown in grayscale (which, trust me, is easier on the eyes than a redscale image). One of these regions, IC 1308 (aka “[H25] X” or “Hubble X”), is rougly 11 times the size of M42 in our own Milky Way.

This image is a do-over of this this old version. (By the way, I have no idea why that old version came out so green—the color in the current version is likely to be far more accurate.) A higher-resolution image is also available. North is up.