In a recent post I talked about a photo session in which I captured images of Orion using a wide-angle lens. My next goal was to use a telephoto lens to zoom in on specific areas. My first effort did not go well. It was cold and windy. My attempts to get the star tracker aligned were mostly unsuccessful — because of the cold and wind. And the lens I used (Nikon 200-500mm f/5.6) was too big and heavy for the tracking mount.

I tried again the next night and there was less wind–but it was still cold. This time I used the Nikon 180mm ƒ/2.8 ED AI-S manual focus lens. It is much lighter and easier to focus and it produces a very sharp image by the time it is stopped down to ƒ/4.0. My goal was to capture the Flame Nebula (NGC 2024) and the Horsehead Nebula (Barnard 33) plus one or more stars from Orion’s belt.

Both the Horsehead Nebula and the Flame Nebula are in the constellation of Orion and are part of the much larger Orion molecular cloud complex. (Note: an amusing reference to the “Horace Head Nebula” appears in Isaac Asimov’s “The Stars, Like Dust“. Check it out!) The Flame Nebula is an emission nebula while the Horsehead Nebula is a small dark nebula.

I shot 73 one-minute exposures plus the usual assortment of darks, flats, and bias images. The images were stacked using Siril 1.4 with Star Reduction, histogram stretching using rnc-color-stretch, and finally post processed in Lightroom and Photoshop.

The first image is the result with Star Reduction turned on; the second image is without Star Reduction. I like them both.

Nikon D850, Nikon 180mm ƒ/2.8 ED AI-S @ ƒ/4.0, ISO 400, 73 x 60 seconds.