A portrait of the constellation of Orion taken in monochrome in the deep red light of the hydrogen-alpha wavelength using a narrowband filter, to emphasize the vast clouds of interstellar gas within and around Orion. The Orion Nebula is the bright object at lower centre; the Horsehead Nebula below the Belt of Orion is near centre; the bright object at upper left is the Rosette Nebula in Monoceros. The large circular glow at top around the head of Orion is Sharpless 2-264, the Lambda Orionis nebula. The curving arc on our left side of Orion is Sharpless 2-276, aka Barnard's Loop. This is a stack of 24 x 4-minute exposures with the red-sensitive Canon Ra camera at ISO 1600 shooting through the Canon RF28-70mm lens at 50mm and wide open at f/2. The filter was the Astronomik 12nm Ha clip-in filter. This was taken Feb 10, 2022 in bright moonlight with the waxing gibbous Moon just off frame at top, creating some challenging gradients.
This is a portrait of the main nebulosity in Orion in his Sword, including: the Orion Nebula itself (at centre), aka Messiers 42 and 43, and the Running Man Nebula above (aka NGC 1973-5-7). The bright blue star cluster NGC 1981 shines above the Running Man. The subtle reflection nebula NGC 1999 is below M42 but a bit lost amid the other faint and dusty nebulosity. The field of view is 4° by 2.7°. This is a stack of 11 x 6-minute exposures with an Askar FRA500 astrograph (500mm focal length at f/5.5), and stock Canon R6 camera at ISO 800. The camera was not modified and no filters were employed here. I did not take short exposures for the core of the bright Orion Nebula. Some light haze added star glows. Nebulosity is brought out in Photoshop using successive curves with luminosity masks generated by Lumenzia, and with applications of the Nebula Filter action from the PhotoKemi StarTools action set, and Enhance DSO from the Astronomy Tools action set. All alignment and layering was in Photoshop. Taken from home January 26, 2022. Autoguided and dithered with the MGEN3 guider, with LENR dark frame subtraction also applied to each frame in camera to eliminate the edge amp glow the R6 exhibits. It was about -5° C this night.
The Orion Nebula, M42, with its companion nebula M43 to the north, and the blue Running Man Nebula at top (aka NGC 1975), all in a clear but moonlit sky, illuminated by a first quarter Moon, making the sky blue. So this can’t be a very deep image, but it shows the main features visible in a large telescope. The loose open cluster, NGC 1981, is at top — I should have framed this scene a little more north to better include the cluster. This is a blend, using luminosity masks, of three sets of exposures: 8 x 8 minutes for the main image content + 4 x 2 minutes for a mid-level exposure for the core area + 1 x 30-second for the Trapezium area right at the core. This sort of “high dynamic range” blending is necessary for M42 as it contains such a range of brightness that no single exposure can record it all. However, I did not use HDR methods to do the blending, but luminosity masks which are easy to make with one click in Photoshop — Command/Control click on the RGB Channel image — and they allow far greater control of the blending. This sort of exposure blending is needed because while your telescope-aided eye can see the faintest tendrils and the bright quadruple star system, the Trapezium, at the centre with no problem, cameras cannot. At least not in a single exposure. All were with the Astro-Physics Traveler apo refractor at f/6 with the Hotech field flattener and Nikon D750 (not modified) at ISO 200!
