NGC5907 Spiral Galaxy

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2013/05/10 - This galaxy is still work in progress, because I only had one night of data and it needs more. But seeing was great when I shot this image, it was between 2.09" and 2.43", so that's quite good for this location. Too bad it became cloudy during this night. My permanent Sky Quality Meter is working (see weather), so I can check the best value every imaging session.

GC 5907 is a spiral galaxy located approximately 50 million light years from Earth. It has an anomalously low metallicity and few detectable giant stars, being apparently composed almost entirely of dwarf stars. It is a member of the NGC 5866 Group. NGC 5907 has long been considered a prototypical example of a warped spiral in relative isolation. Then in 2006, an international team of astronomers announced the presence of an extended tidal stream surrounding the galaxy that challenges this picture and suggests the gravitational perturbations induced by the stream progenitor may be the cause for the warp. NGC 5907 is also known as the Knife Edge or Splinter galaxy. The galaxy was discovered in 1788 by William Herschel. Supernova 1940A was in this galaxy.

Object information
Name : NGC5907 Spiral Galaxy
Type : Galaxy
Constellation : Draco
Distance : 53.500K light-year
Apparent dimensions : 12.7' x 1.4'
Apparent magnitude : 11.10

Image information
Image date : 2013/05/10
Right ascension : 15:15:53.830
Declination : 56°19' 41.85"
Focal length : 1381.72 mm
Focal ratio : f/5.44
Image resolution : 0.806 arcsec/pixel
Field of view : 44' 12.9" x 33' 5.5"
Sky quality : 19.59 mag/arcsecond2
Sensor temperature : -30°C
Light frames : 3 hours, 20 minutes total exposure time
8x 600 sec. luminance unbinned
4x 600 sec. RGB unbinned
Image acquisition with CCDAutoPilot and Maxim DL
Auto-guiding with Maxim DL
Auto-focusing with FocusMax
Bias frames : 100x unbinned
Dark frames : None
Flat frames : 6x luminance unbinned
6x RGB unbinned
Twilight flats with CCDAutoPilot
Processing : PixInsight for calibration, alignment and integration.
Adobe Photoshop CS6 for final touch.

Equipment information
Telescope : Robtics 10" 2000mm f/8 Ritchey Chretien
Corrector : Astro-Physics CCDT67 Focal Reducer
Focuser : Moonlite CS Ritchey Chretien focuser with high resolution stepper motor
Mount : ASA DDM60 Pro direct drive german equatorial mount controlled with AutoSlew
Camera : QSI 683wsg-8 cooled CCD camera with Kodak KAF-8300 sensor and Off Axis Guide (OAG) port
Guidecamera : Starlight Xpress Lodestar autoguider
Filters : Astrodon Tru-Balance E-Series LRGB & Astrodon 3nm H-α, 3nm O-III, 3nm S-II and 3nm N-II
Observatory site : Etten-Leur, The Netherlands