M63 Sunflower Galaxy

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2013/04/29 - I tried to capture this galaxy for 4 nights, but horrible seeing (> 3") and clouds ruined the sessions. So I selected the best data (FWHM < 3") and processed it. Because the flatfieldpanel caused strange patterns, I now tried sky (twilight) flats, that seems to work better.

The Sunflower Galaxy (also known as Messier 63, M63, or NGC 5055) is a spiral galaxy in the constellation Canes Venatici consisting of a central disc surrounded by many short spiral arm segments. The Sunflower Galaxy is part of the M51 Group, a group of galaxies that also includes the Whirlpool Galaxy (M51).

The Sunflower Galaxy was discovered by Pierre M├ęchain on June 14, 1779. The galaxy was then listed by Charles Messier as object 63 in the Messier Catalogue. In the mid-19th century, Lord Rosse identified spiral structures within the galaxy, making this one of the first galaxies in which such structure was identified. In 1971, a supernova with a magnitude of 11.8 appeared in one of the arms of M63.

Object information
Name : M63 Sunflower Galaxy
Type : Galaxy
Constellation : Canes Venatici
Distance : 37M light-year
Apparent dimensions : 12'.6 x 7'.2
Apparent magnitude : 9.30

Image information
Image date : 2013/04/29, 2013/04/28, 2013/04/27, 2013/03/15
Right ascension : 13:15:48.402
Declination : 42°1' 47.11"
Focal length : 1381.86 mm
Focal ratio : f/5.44
Image resolution : 0.806 arcsec/pixel
Field of view : 43' 3.3" x 31' 50.3"
Sensor temperature : -30°C
Light frames : 4 hours, 50 minutes total exposure time
7x 600 sec. luminace unbinned
12x 600 sec. red unbinned
6x 600 sec. green unbinned
4x 600 sec. blue 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 : 5x luminance unbinned
5x RGB unbinned
Created with Gerd Neumann Aurora flatfield panel and twilight sky flats
Processing : PixInsight for calibration (bias frames and flat frames), 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