| Date 2015/11/16 Observation place My permanent observatory in Longueuil in white light pollution zone |
Technical
| Telescope | Orion 80ED refractor - Diameter 80 mm (3,15 ''), focal length 480 mm, f / 6 |
| Mount | Celestron CGEM |
| Imaging camera | Atik 383 L + monochrome regulated at -20o Celsius |
| Autoguiding camera | ZWO ASI 120MM with one optical splitter |
| Auto Guidance Accuracy (RMS) | 3,63 ″ of arc (7,25 ″ of arc in total) |
| Image type | Hubble Palette: HaSII (SII-Ha-OIII) Luminance image with the Ha and SIII filter |
| Exhibition | 10 minute images: SII (9 x 10 'bin 2 × 2), Ha (10 x 10' bin 2 × 2) and OIII (10 x 10 'Bin 2 × 2) ------------ 30 second images: SII (10 x 30 '' bin 2 × 2), Ha (10 x 30 '' bin 2 × 2) and OIII (10 x 30 '' Bin 2 × 2) |
| Image acquisition software | Maxim DL |
| Guidance software | PHD Guiding 2 |
| Pretreatment | Maxim DL |
| Treatment | Photoshop and PixInsight |
| Specific treatment | Hubble Palette |
Object description
| Object type | Emission nebula and open cluster "The Great Orion Nebula" |
| Constellation | Orion |
| Visual magnitude | 4 |
| Distance | 1350 light years |
| Diameter | 33 light years |
| Dimension seen from Earth | 60 x 60 arc minutes |
| M42 is called The Great Nebula of Orion. It represents a luminous cloud of ionized gas illuminated by the hot young stars that occupy its central region. It took until 2007 to realize that the nebula is about 1350 light-years from Earth instead of the 1500 light-years previously estimated. It contains a very young open cluster containing many stars. M43 is part of the Orion Large Nebula complex. Visually, she seems detached from it because of a veil of dust that obscures their bond. In a sky with little light pollution, M42 is one of the easiest celestial objects to observe. By pointing a telescope, a telescope or even good binoculars, the nebula appears easily. A low magnification (between 30 and 60 times) makes it possible to observe it as a whole. A greater magnification, of the order of 100 to 200 times, makes it possible to observe the stars which compose it. It is a real pleasure for amateur astronomers, as it is easy to find and reveals a lot of detail even in small diameter instruments. With a telescope 114 mm in diameter, it has the shape of a "bird". We can see a diffuse white spot with shapes, and a kind of shadow in the center. With a 200mm telescope, it looks really bright. Good atmospheric conditions sometimes suggest the colors of the nebula. Due to its favorable magnitude, it is possible to use filters improving the contrast (OIII for example) and thus to distinguish more details. To combat the light pollution of my observation site (which is in the white zone) and to bring out even more the very beautiful contrasts and nuances of the nebula, I used narrow-band filters with the association called the Hubble palette. (SII-Ha-OIII). This combination of color filters served to bring out in the image the chemical distribution of the main elements of the nebula by offering a wide variety of colors. |
| Richard Beauregard Sky Astro - CCD My impression "We cannot be alone in this gigantic universe" |