NGC4725 Barred Spiral Galaxy

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2013/05/04 - It took me 1.5 night to create this image, during the second night it became cloudy halfway the session. Seeing varied a bit, it was 2.31" at best. It also was a bit humid, so transparency could be better. The two sessions were completely automized with CCDAutoPilot, Maxim DL, Autoslew and FocusMax. NGC 4725 is the main object, but NGC 4747 and NGC 4712 also show some detail.

NGC 4725 is an intermediate barred spiral galaxy about 40 million light-years away in the constellation Coma Berenices. NGC 4725 is a Seyfert Galaxy, suggesting an active galactic nucleus containing a supermassive black hole.

Object information
Name : NGC4725 Barred Spiral Galaxy
Type : Galaxy
Constellation : Coma Berenices
Distance : 40M light-year
Apparent dimensions : 10.7' x 7.6'
Apparent magnitude : 10.10

Image information
Image date : 2013/05/04, 2013/05/03
Right ascension : 12:50:46.923
Declination : 25°37' 6.28"
Focal length : 1382.02 mm
Focal ratio : f/5.44
Image resolution : 0.806 arcsec/pixel
Field of view : 44' 19.6" x 33' 15.5"
Sensor temperature : -30°C
Light frames : 8 hours, 10 minutes total exposure time
13x 600 sec. luminance unbinned
12x 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 : 12x luminance unbinned
12x RGB unbinned
Twilightflats; 6x at dusk and 6x at dawn
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