NGC2244 Rosette Nebula

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2013/02/11 - I improved the collimation of the RC. Still seeking for optimum parameters for CCDAutoPilot, FocusMax and Autoslew, but I'm getting in the right direction. This data is shot during two separate nights.

The Rosette Nebula (also known as Caldwell 49) is a large, circular H II region located near one end of a giant molecular cloud in the Monoceros region of the Milky Way Galaxy. The open cluster NGC 2244 (Caldwell 50) is closely associated with the nebulosity, the stars of the cluster having been formed from the nebula's matter.

The complex has the following NGC designations:
NGC 2237 – Part of the nebulous region (Also used to denote whole nebula)
NGC 2238 – Part of the nebulous region
NGC 2239 – Part of the nebulous region (Discovered by John Herschel)
NGC 2244 – The open cluster within the nebula (Discovered by John Flamsteed in 1690)
NGC 2246 – Part of the nebulous region

The cluster and nebula lie at a distance of some 5,200 light-years from Earth (although estimates of the distance vary considerably, down to 4,900 light-years.) and measure roughly 130 light years in diameter. The radiation from the young stars excite the atoms in the nebula, causing them to emit radiation themselves producing the emission nebula we see. The mass of the nebula is estimated to be around 10,000 solar masses.

It is believed that stellar winds from a group of O and B stars are exerting pressure on interstellar clouds to cause compression, followed by star formation in the nebula. This star formation is currently still ongoing.

Object information
Name : NGC2244 Rosette Nebula
Type : Nebula
Constellation : Monoceros
Distance : 5.200 light-year
Apparent dimensions : 1.3º x 1.3º
Apparent magnitude : 9.00

Image information
Image date : 2013/02/11, 2013/02/08
Right ascension : 6:31:6.259
Declination : 5°3' 2.69"
Focal length : 1381.59 mm
Focal ratio : f/5.44
Image resolution : 0.806 arcsec/pixel
Field of view : 44' 20.4" x 33' 11.3"
Sky quality : 19.76 magnitude/square arcsecond
Sensor temperature : -25°C
Light frames : 4 hours, 30 minutes total exposure time
6x 900 sec. hydrogen-alpha unbinned
6x 900 sec. oxygen-III unbinned
6x 900 sec. sulfur-II unbinned
Image acquisition with CCDAutoPilot Pro and Maxim DL Pro
Auto-guiding with Maxim DL
Auto-focusing with FocusMax
Bias frames : 100x unbinned
Dark frames : Bap pixel map
Flat frames : No flat frames
Processing : PixInsight for calibration (bias frames, bad pixel map 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