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5
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Click the image for a wide field view. (3312 x
2208 - 1.66 MB)
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Instrument |
12.5" RCOS @
~ f/9 (2880 mm fl) at 0.64 arcsec/pixel. Shown at 0.64 arcsec/pixel. |
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Mount |
Paramount ME |
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Camera |
SBIG STL-11000 w/
FW8 filter wheel & AstroDon Gen-2 LRGB filters. |
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Acquisition Data |
1/19/2018 to 4/8/2018 Chino Valley, AZ. with CCD Commander & CCDSoft. AOL
guided |
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Exposure |
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Lum |
900 min (30 x
30 min. each) Bin 1x1 |
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RGB |
675 min (15 x
15 min. each) Bin 2x2 |
eXcalibrator RGB ratios are 1.00,
1.11 & 1.27 |
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Software & Processing Notes
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CCDSoft, CCDStack,
PixInsight, Photoshop CS6.
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eXcalibrator
v6.1 for (g:r),(b:r) color balancing, using
75 stars from the Pan-STARRS database.
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CCDBand-Aid to repair
KAI-11000M vertical bars.
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CCDStack to
calibrate the sub exposures.
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PixInsight to
register, data reject, mean combine the sub exposures and
create the LRGB image. Also for
gradient removal, non-linear stretching with HistogramTransformation,
color saturation
and increased galaxy core detail with HDRMultiscaleTransform.
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PhotoShop layers
for selectivly adding the enhanced galaxy core data, selective
sharpening, and background noise reduction.
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Noiseware 5, a PhotoShop plug-in.
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Comment
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Shown rotated 90°
counter clock-wise.
NGC 2685 (the Helix
Galaxy) is a lenticular and polar ring Seyfert galaxy in the
constellation Ursa Major, at a distance of about 45 million
light-years. Polar ringed galaxies are quite rare and attract great
interest. The rings are probably captured material from another
galaxy.
Also visible is an external ring surrounding the entire galaxy. This
may be true ring or a complete shell.
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