Celestial hemisphere:  Southern  ·  Constellation: Orion (Ori)  ·  Contains:  41 the01 Ori  ·  42 c Ori  ·  43 the02 Ori  ·  44 iot Ori  ·  45 Ori  ·  De Mairan's nebula  ·  Great Nebula in Orion  ·  Hatysa  ·  LBN 974  ·  LBN 977  ·  LDN 1640  ·  M 42  ·  M 43  ·  NGC 1973  ·  NGC 1975  ·  NGC 1976  ·  NGC 1977  ·  NGC 1980  ·  NGC 1982  ·  Sh2-279  ·  Sh2-281  ·  The star 42Ori  ·  The star 45Ori  ·  The star θ1Ori  ·  The star θ2Ori  ·  The star ιOri
Getting plate-solving status, please wait...
M42, Great Orion Nebula, Hα False Color Animation, 2 Jan 2014, David Dearden
Powered byPixInsight

M42, Great Orion Nebula, Hα False Color Animation, 2 Jan 2014

Equipment

Loading...

Acquisition details

Loading...

Description

Despite a nearby nearly-full Moon, I decided to try narrowband imaging of the Orion Nebula knowing that clouds were forecast after midnight. Pointed my scope in the general direction and did a plate solve; I was way off, but the PicGoto took me right to M42 anyway. Aligned the shot to match my 9 Mar 2013 RGB image so that I can combine with that later. Began with some short exposures to deal with the huge dynamic range presented by this object. Tried a 600 s exposure, but that overexposed too much of the nebula without bringing up the fringes very much relative to 300 s, so I backed off to 300 s. Guiding performance was terrible; I'm still having balance issues that are not helped by the viscosity of my mount lubricants at these low temperatures. The clouds came early and quite suddenly, so I got less data than desired. It is interesting to compare this with RGB because the comparison indicates how much of the nebula is reflection vs. emission; a lot of the Running Man, for example, doesn’t show up in Hα and therefore is not Hα emission; it must be more reflection (I guess it must be farther away from the hot Trapezium stars and/or contains more non-hydrogen dust).

Date: 2 Jan 2015

Subject: M42 and friends, Great Nebula in Orion

Scope: Orion ST80 + Antares 0.5x telereducer

Filter: Baader 7 nm Hα

Mount: CG-5 (Synta motors, PicGoto Simplificado)

Guiding: 9x50 Finder/Guider + DSI Ic + PHD 2.4.1 (Win 7 ASCOM)

Camera: DSI IIc no cooling (-8.5 to -11.5 °C)

Acquisition: Nebulosity 3.2.1, no dither

Exposure: 30x15+35x60+32x300 s

Stacking: Neb 3, bad pixel map, bias included, no flats, extract R, histogram match, square, trans+rot align, 1.5 SD stack.

Processing: StarTools 1.3.5.289 Crop; Develop 74.99%; HDR:Core Reveal (short exposures) Optimize (300 s); Deconvolute: 4.0 pix; Track 3.0 pix; Magic 1 pix. Photoshop CC 2014 + Carboni Astronomy Tools Hα false color black sky; Astroframe.

Comments

Sky plot

Sky plot

Histogram

M42, Great Orion Nebula, Hα False Color Animation, 2 Jan 2014, David Dearden