SaratogaSkies Jim Solomon's Astropics

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IC 1287 (Reflection Nebula)   [obsolete]

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 1600
Total Exposure: 0hrs, 20min
Date: 7/20/2004, ~11pm PDT
Location: Saratoga, CA, USA
Acquisition: DSLRfocus
Focus: DSLRFocus
Dithering: None
Guiding: None

Processing:

  • IRIS: Dark subtraction, flat frame, registration, Kappa-Sigma stacking, and noise reduction
  • Photoshop: Color mixing, crop (2/3 x), image scale (3/8 x), JPG conversion

Image Description:

IC 1287 is a very faint reflection nebula in Scutum. In this image it is just barely visible as a blue "halo" around the bright star in the center in the field (SAO 161569). This image could have used more exposure, but tracking problems ruined most of the frames I shot. The transparency and seeing were pretty lousy too. Those diffraction spikes look cool, though, don't they!? <g> This is approximately 2/3's of the full frame, scaled for display on the web. North is up.

 
C/2004 Q2 [Machholz] (Comet)
SaratogaSkies Jim Solomon's Astropics

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C/2004 Q2 [Machholz] (Comet)

Image Details:

Camera: Canon Digital Rebel (300D)
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: 65 x 2min @ ISO 800
Total Exposure: 2hrs, 10min
Date: 2/1/2005 7:24:34 PM (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, flat field, registration, cropping
  • JimP: N through M stacking, sequence ASINH stretching
  • Photoshop: Compositing, levels, image scale, JPG conversion
  • Premiere: AVI creation from individual frames

Image Description:

This is my second attempt at Comet C/2004 Q2 (Machholz), named after the San Jose Astronomical Association (SJAA) member Don Machholz who discovered it. See the ST80 image for a description of the processing steps and for a comparison picture. Perhaps the best-resolved object in this picture is Trumpler 3, the small Open Cluster of stars in the lower left (above the copyright notice).

To process this image, I used the technique described in this thread in the CloudyNights Forum. The difference is that I did all the machinations after ASINH stretching each individual frame, whereas I believe the author worked on the linear frames and only stretched the final result.

I had some major problems with the capture of this image:

  1. The ED80 was severely out of collimation when this was shot.
  2. The ED80 with Celestron f/6.3 Reducer has some field flatness issues, causing aberrations beyond the center of the frame. The collimation problem mentioned above exacerbates this.
  3. The framing of the comet, while asthetic in that there's "room" for both the ion and debris tails, places most of the interesting detail outside the "sweet spot" of the ED80 + focal reducer, making the signal to noise of the ion tail (in particular) quite low.
  4. There was tons of light pollution to the NorthWest, the direction this was shot on that night.
  5. My polar alignment was less than marvelous, causing roughly 0.5? of field rotation over the course of the imaging session. While IRIS is quite capable of derotating the frames, part of me believes that this function causes a loss of detail and an overall decrease in signal to noise.
  6. The comet was actually moving twice as fast (in arc-seconds per minute) than predicted by The Sky software. Had I known this, I might have gone for even shorter integrations (1min) at higher ISO (1600), since that would have been less than a pixel's worth of movement over the course of each frame, theoretically resulting in less blurring of each individual frame since I was guiding on a star, not the comet.
  7. The transparency that night was pretty awful.

So, that's my sob story, and all of the above show in the (lack of) detail in this image. Sniff. The movie (1MB AVI) is pretty cool and worth checking out. North is up.

 
Jupiter
SaratogaSkies Jim Solomon's Astropics

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Jupiter   [obsolete]

Image Details:

Camera: Canon Digital Rebel (300D)
Mount: Celestron AS-GT
Scope: Celestron C8-N (8" f/5 Newtonian)
Configuration: Eyepiece Projection
Additional Optics: Celestron "Kit" 9mm Plössl
Filter: None
Effective Focal Length: 6650mm
Effective Focal Ratio: f/33.2
Exposure: 20 x 0.3 second @ ISO 100
Date: 6/21/2004, 9:41pm PDT
Location: Saratoga, CA, USA
Acquisition: Manual
Focus: Manual
Dithering: None
Guiding: None

Processing:

  • IRIS: registration, stacking, wavelet processing, cropping
  • Photoshop: Saturation, levels, JPG conversion

Image Description:

A decent Jupiter picture, but DSLRs just can't compete with webcams for planetary imaging in my opinion. The dark spot in the center of the North Equatorial Band is Jupiter's moon Ganymede. The pale, reddish patch on the far right side of the South Equatorial Band is Jupiter's Great Red Spot, affectionately known these days as the Great Pale Spot, since it's color has faded over the years. This is a crop of the full-size image. Earth's North is up, so Jupiter appears tilted counter-clockwise by 23.5°.

 
M17 (Omega Nebula)
SaratogaSkies Jim Solomon's Astropics

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M17 (Omega Nebula)

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: 18 x 4min @ ISO 400
Total Exposure: 1hrs, 12min
Date: 8/21/2006 9:28:12 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: Levels, cropping, JPG conversion

Image Description:

This is M17, aka, the Swan/Checkmark/Horseshoe/Omega Nebula in the constellation of Sagittarius. This is a do-over of my ancient version, one of the first images I captured with my (unmodified) Digital Rebel back in 2004. The current image is decent, considering the horrible conditions under which it was captured: the transparency and seeing were quite awful, and all the equipment was dripping with dew. Not bad considering. A higher resolution image is also available. North is up.

 
Jupiter and Moons
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>]

 
M106 (Spiral Galaxy)
SaratogaSkies Jim Solomon's Astropics

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M106 (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: 34 x 8min @ ISO 400
Total Exposure: 4hrs, 32min
Date: 5/8/2007 9:57:31 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
  • PixInsight LE: gradient removal
  • JimP: Flat field, Kappa-Sigma Stacking, White balance, ASINH stretching
  • Photoshop: Sharpening, levels, cropping, JPG conversion

Image Description:

This is M106, a spiral galaxy in the constellation of Canis Venatici. M106 is a Seyfert Galaxy, suggesting an active galactic nucleus containing a supermassive black hole. A higher resolution image is also available. North is up.

 
M109 (Barred Spiral Galaxy)
SaratogaSkies Jim Solomon's Astropics

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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.