| Date: 2017/08/21 Observation place My permanent observatory in Longueuil in white light pollution zone |
Technical
| Telescope | Orion 80ED refractor - Diameter 80mm, focal length 480mm, 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) | 1,35 '' of arc (2,7 '' of arc in total) |
| Image type | Ha (HaR-VsB) Vs: Synthetic green HaR: red layer with Ha and red filters) |
| Exhibition | Ha (10 x 10 'bin 2 × 2), Red (15 x 2' Bin 2 × 2) and Blue (12 x 2 'Bin 2 × 2) |
| Image acquisition software | Maxim DL |
| Guidance software | PHD Guiding 2 |
| Pretreatment | Maxim DL |
| Treatment | Photoshop and PixInsight |
| Specific treatment | Synthetic green layer |
Object description
| Object type | Emission nebulae containing "The Pelican Nebula" |
| Constellation | Swan |
| Visual magnitude | 8 |
| Distance | 1800 light years |
| Diameter | 30 light years |
| Dimension seen from Earth | 80 x 70 arc minutes |
| Nebula IC5070 contains nebula IC5067, referred to as the Pelican Nebula which is due to its resemblance to the bird of the same name. It can be seen at the top of the nebula in the image. See annotated image here. IC5070 is 2,5 times the diameter of the Moon. So it's a very large nebula. Several studies have been done on this nebula because there is a particularly active mixture of star formation caused by evolving gas clouds. Light from energetic young stars slowly changes from a cold gas to a warm one causing an ionization front gradually going out of the nebula. This great activity promotes the formation of future planets and, who knows, will allow the creation of life! To observe it visually, you need a sky without light pollution and a telescope with a large field of view and a low magnification eyepiece. For this image, I used an exposure with the H-Alpha filter as the luminance image. It was used to get the majority of the signal from these nebulae, which is in alpha hydrogen. In addition, this filter effectively blocks the significant light pollution from my observation site (located in the city of Longueuil!). To produce the color image, I used the H-Alpha association with the red filter for the red channel. A blue filter was used for the blue channel. I produced a synthetic green with the Ha + red and blue filters. This saved exposure time for the green channel. The RGB color component is therefore summarized by the acronym (Ha + R) VsB. This association served above all to bring out the natural colors of the stars. |
| Richard Beauregard Sky Astro - CCD My impression "We cannot be alone in this gigantic universe" |