NGC2175 Monkey Head Nebula

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2013/01/12 - Finally a clear night after ages of clouds and rain. I also tested the ASA DDM in combination with CCD AutoPilot v5 with this image. The only thing a did manually was focusing (no time to get FocusMax up and running). Please note that North is down, so the head is up. Still some collimation errors I need to look at. I hope to add the correct star colors soon.

Open Cluster NGC 2175 (also known as OCL 476 or Cr 84) is an open cluster in the Orion constellation. It was discovered by Giovanni Batista Hodierna before 1654 and independently discovered by Karl Christian Bruhns in 1857. NGC 2175 is at a distance of about 6,350 light years away from Earth. The nebula surrounding it is Sharpless catalog Sh 2-252.


Object information
Name : NGC2175 Monkey Head Nebula
Type : Nebula
Constellation : Orion
Distance : 6.350 light-year
Apparent dimensions : 18' x 18'
Apparent magnitude : 7.00

Image information
Image date : 2013/01/12
Right ascension : 6:9:39.064
Declination : 20°29' 9.08"
Focal length : 1383.62 mm
Focal ratio : f/5.45
Image resolution : 0.805 arcsec/pixel
Field of view : 44' 16.5" x 33' 12.4"
Sensor temperature : -25°C
Light frames : 3 hours total exposure time
3x 1200 sec. hydrogen-alpha unbinned
3x 1200 sec. oxygen-III unbinned
3x 1200 sec. sulfur-II unbinned
Image acquisition with CCD AutoPilot and Maxim DL
Auto-guiding with Maxim DL
Bias frames : 100x unbinned
Dark frames : Bap pixel map
Flat frames : no flats
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