This is composition taking in many of the bright and not so bright nebulas in and around the Sword and Belt of Orion. At bottom is the bright Orion Nebula, Messier 42. Above it is the bluish Running Man Nebula, NGC 1973-5-7. At centre is the famous dark Horsehead Nebula, B33, silhouetted against the bright glow of IC 434. Above it, and above the blue star Alnitak is the pinkish Flame Nebula, NGC 2024. At top left is the reflection nebula complex of Messier 78 and NGC 2071. Numerous other small patches of nebulosity shine around the Belt stars at right of centre. The large Barnard's Loop, Sh-2-276, just sneaks into the corner of the frame at top left. This is a blend of filtered and unfiltered images: a stack of 8 x 8-minute exposures through an Optolong L-Enhance filter blended with a stack of 12 x 8-minute exposures without a filter, with the filtered shots at ISO 3200 and unfiltered shots at ISO 800. Stacks of 4 x 2-minute at ISO 800 and 4 x 2-minute at ISO 200 are also blended in with luminosity masks to retain the details in the bright core of the Orion Nebula, and to shrink the stars. All were with the Canon EOS Ra mirrorless camera shooting through the William Optics RedCat 51mm astrograph at f/5 (250mm focal length). The unfiltered shots were taken the night after the filtered shots, as incoming haze and ice fog cut short the shoot on the first night, January 9, 2021, and prevented more filtered shots (for lower noise) without haze. As it is, some haze surrounds the stars. The RedCat is equipped with the Starizona filter drawer accessory to make it easier to swap the filter in and out without affecting camera position. This was on the Astro-Physics Mach1 mount and guided with the made-in-Hungary Lacerta MGEN3 autoguider which also controlled the camera and applied a dithering motion between each shot to help remove thermal noise. No dark frames were taken nor was Long Exposure Noise Reduction applied in camera, though it was -5° C these nights, chilly but mild for January here in Alberta. All stacking, aligning and mean or median combining (the latter to eliminate some geosat trails) was done in Photoshop 2021. Luminosity masks to enhance the faint nebulosity and apply star masks where needed were created with the Lumenzia extension panel. The masking helps compress the dynamic range, allowing the faintest nebulosity to be enhanced without blowing out the bright highlights like the core of M42. But inevitably, the Orion Nebula ends up looking dimmer than it really is in relation to the other nebulas in the field.
The region of the summer Milky Way in northern Cygnus containing a rich collection of bright nebulas: the North America Nebula at centre and the Gamma Cygni complex at right, plus the dark nebulas Le Gentil 3, the Funnel Cloud Nebula at upper left, the Northern Coal Sack at centre, and the finger-like B168 at lower left. The bright star at centre is Deneb. M39 is at lower left. This is a stack of 6 x 3-minute exposures with the 85mm Rokinon lens at f/2.8 and Canon 6D MkII at ISO 800, on the Sky-Watcher Star Adverturer tracker. An additional exposure taken through a Kenko Softon A filter adds the star glows. Taken on a very clear night from home August 1, 2019. The camera was not filter-modified so the red nebulas don’t stand out as much as they should.
The nebulas of Orion in the Belt and Sword of Orion area. Including M42, Orion Nebula (lower centre), Barnard's Loop (at left), M78 at upper left (small reflection nebula), Horsehead Nebula (above centre) and NGC 2024 (above Horsehead). There is faint reflection nebulosity at right -- the frame does not extend right far enough to show the Witchhead Nebula near Rigel. This is a stack of 5 x 4 minute exposures at f/2.8 with the Canon 135mm L series lens and filter-modified Canon 5D MkII at ISO 640. One exposure had soft stars from high altitude haze which added the glows around stars naturally. Shot from Coonabarabran, Australia, December 13/14, 2012.
