SaratogaSkies Jim Solomon's Astropics

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Jupiter and Moons   [obsolete]

Image Details:

Camera: Canon Digital Rebel (300D)
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: 2844mm
Effective Focal Ratio: f/54.2
Exposure: 9 x 1/2 second @ ISO 800
Date: 6/22/2004, 9:28pm PDT
Location: Saratoga, CA, USA
Acquisition: Manual
Focus: Manual
Dithering: None
Guiding: None

Processing:

  • IRIS: Dark subtraction, flat field, registration, stacking
  • Photoshop: Compositing of IRIS moons and Jupiter images, sharpening, saturation, scale, JPG conversion

Image Description:

An interesting shot of Jupiter and the four Galilean moons. The f/ratio is so high because I put the aperture mask on the end of the telescope, effectively turning the 200mm obstructed Newtonian into a 52.5mm unobstructed offset-Newtonian. For those familiar with telescope optics, the Newtonian design has a secondary mirror in the path of the light that hits the primary mirror, and this so-called "obstruction" can cause a loss of contrast, especially on objects like planets that have low contrast to begin with. By putting the aperture mask on, the secondary is out of the path of the light hitting the primary (now effectively only 52.5mm instead of 200mm), preserving all of the contrast. However, the lower effective aperture could conceivably cause a loss of resolution, but since this is a relatively low effective focal length (2844mm), that loss of resolution isn't evident, and is overwhelmed by the seeing conditions in any case. [In retrospect — what was I thinking!?!? <grin>]

 
M31 (Andromeda Galaxy)
SaratogaSkies Jim Solomon's Astropics

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M31 (Andromeda 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: Orion ED80 (80mm f/7.5 APO Refractor)
Configuration: Focal Reduced
Additional Optics: Celestron F/6.3 Reducer/Corrector (0.63x)
Filter: None
Effective Focal Length: 420mm
Effective Focal Ratio: f/5.2
Exposure: 25 x 8min @ ISO 400
Total Exposure: 3hrs, 20min
Date: 10/11/2005 12:42:47 AM PDT (start)
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, registration, gradient removal
  • JimP: Flat field, Kappa-Sigma Stacking, White balance, ASINH stretching
  • Neat Image: Noise removal
  • Photoshop: Levels, cropping, JPG conversion

Image Description:

This is my second attempt at M31, this time with a focal-reduced ED80 and the Modified 350D. This was a test to see if I could run the equipment overnight while I slept. Seems to have worked pretty well, but without dithering (which I still do manually), there was a large amount of residual pattern noise after calibration, registration, and stacking. While Neat Image did a decent job of removing that pattern noise, I really need to look into something like GADfly (see the Files section of Digital_Astro) to automate inter-exposure dithering. This is the full frame, shrunk for display on the web. A higher-resolution version of this image is also available, as is my previous attempt from last year with an unmodified camera. North is right.

 
Jupiter Moon Animation
SaratogaSkies Jim Solomon's Astropics

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Jupiter Moon Animation

Image Details:

Camera: Mofidied Philips ToUcam Pro II (840k): Color RAW Hack
Mount: Celestron AS-GT
Scope: Orion ED80 (80mm f/7.5 APO Refractor)
Configuration: Focal Reduced
Additional Optics: William Optics 2" APO 0.8x Reducer/Field Flattener
Filter: None
Effective Focal Length: 480mm
Effective Focal Ratio: f/6
Exposure: 256 x 1/500 sec @ Gain = 10% (Jupiter), 48 frames of 45 x 1/25 sec @ Gain = 27% (Moons)
Date: 7/7/2006, 9:52 PM PDT
Location: Saratoga, CA, USA
Acquisition: Philips VRecord
Focus: Manual
Dithering: None
Guiding: None

Processing:

  • IRIS: AVI conversion, CFA conversion, Registration, Best-frame selection, Drizzle Stacking (2x), Wavelet processing, FFT filtering
  • Photoshop:Compositing
  • Image Ready: Animation

Image Description:

This is a time-lapse animation of Jupiter's moons. Each frame in the animation is separated by 2min of "real time", and consists of a stack of 45 exposures. Properly exposing the moons, however, resulted in an over-exposed Jupiter. So, I shot separate exposures of Jupiter and composited the whole mess in Photoshop, then used ImageReady to assemble the animation. Earth's north is up.

 
IC 410 (Tadpole Nebula)
SaratogaSkies Jim Solomon's Astropics

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IC 410 (Tadpole 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: {3 SII, 3 Hα, 2 OIII} × 32min @ -30°C
Total Exposure: 4hrs, 16min
Date: 2/4/2008 8:41 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: Neil's Trick, JPG conversion
  • Neat Image: Noise reduction

Image Description:

This is IC 410, aka, the “Tadpole Nebula”, an emission nebula and open cluster (NGC 1893) in the constellation of Auriga. This is my first attempt at automation with CCD Commander. I made a bunch of newbie mistakes, but eventually got it up and running.

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.

I'm still fighting some star trailing/smearing in my images with the new camera/scope/mount, as yet undiagnosed. Thanks much to Neil Flemming's Trick, I was able to reduce that smearing. A higher resolution image is also available. North is up.

 
Moon, Saturn, and The Twins
SaratogaSkies Jim Solomon's Astropics

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Moon, Saturn, and The Twins

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

Image Details:

Camera: Canon Digital Rebel (300D)
Mount: None
Scope: Canon EF 28mm - 80mm f/3.5 - f/5.6 IV USM lens
Configuration: Prime Focus
Additional Optics: n/a (Prime)
Filter: None
Effective Focal Length: 80mm
Effective Focal Ratio: f/5.6
Exposure: 8 x 1 sec @ ISO 100; 3 x 1/125 sec @ ISO 100
Date: 1/23/2005, 7:36pm PST
Location: Saratoga, CA, USA
Acquisition: Manual
Focus: Manual
Dithering: None
Guiding: None

Processing:

  • IRIS: RAW Conversion, Registration, Stacking
  • Photoshop: Compositing, Levels, Image Size

Image Description:

This is a widefield shot of a 98.33% full Moon near Castor (upper left), Pollux (lower left), and Saturn (lower-right). Castor and Pollux are the two brightest stars in the constellation of Gemini, The Twins. Mouse-over the image above to see annotations and to see the outline of the Gemini constellation. This is a composite of a stack of 1" exposures for the background stars and Saturn, and a stack of 1/125" exposures of the Moon. Compositing was done in Photoshop. Zenith is up (North is roughly in the direction of the line connecting the Moon to Castor).