| Date 2012/01/16 Observation place French alps |
Technical
| Telescope | TMB Fluorite Triplet - Diam. 175 mm (7 ″), foca. 1400mm, f / 8 |
| Mount | Paramount ME |
| Imaging camera | SBIG STL 11K AO-L regulated at -20o Celsius |
| Image type | Ha (RGB) |
| Exhibition | Ha (10 x 7,5 'bin 2 × 2), RGB (4 x 3' bin 3 × 3 each) |
| Pretreatment | Maxim DL |
| Treatment | Photoshop and PixInsight |
Object description
| Object type | Emission nebula containing "The Horse's Head Nebula" |
| Constellation | Orion |
| Visual magnitude | 5 |
| Distance | 1600 light years |
| Diameter | ? light years |
| Dimension seen from Earth | 60 x 14,3 arc minutes |
| Nebula IC434 is a large, low-brightness nebula that contains Horse Head Nebula B33 (from the Bernard catalog). Although its overall visual magnitude is 5, it is mostly due to the very bright stars that compose it. The very beautiful red and blue colored gas clouds are much darker and thus difficult to perceive in a telescope. These gases and dust appear clearly in long exposure photos. On the other hand, to detect them visually, you need a large telescope and a very dark observation site. For the photos, it is necessary to take into account the strong magnitude of the star Alnitak (1,79), which risks being strongly overexposed and thus hamper the results. In the photo, this star is at the left end in the center of the image. I managed not to overexpose it by judiciously using Photoshop's curves. |
| Richard Beauregard Sky Astro - CCD My impression "We cannot be alone in this gigantic universe" |