Orion in February

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.

Flame Nebula and Horsehead Nebula in the constellation Orion with Star Removal.
Flame Nebula and Horsehead Nebula in the constellation Orion with Star Removal.
Flame Nebula and Horsehead Nebula in the constellation Orion.
Flame Nebula and Horsehead Nebula in the constellation Orion.

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.

Orion in January

One of my goals this month was to capture the constellation Orion using a wide angle lens. Several months ago I purchased the Tamron 35mm f/1.4 Di USD lens. This is a very good wide-angle lens for astrophotography because the stars remain sharp in the corners. I have written about this lens in a previous post.

Orion and neighboring gas clouds and nebula.
Orion and neighboring gas clouds and nebula.
Orion and neighboring gas clouds and nebula with labels.
Orion and neighboring gas clouds and nebula with labels.

A good reason to photograph Orion with a wide angle lens is the abundance of interesting objects that are near and surround Orion. These include the Orion Molecular Cloud Complex, the Witch Head Nebula, Rosetta Nebula, Flame Nebula, and Barnards Loop, among others.

A screen shot from the Stellarium application showing Orion and the field of view with a 35° lens.
A screen shot from the Stellarium application showing Orion and the field of view with a 35° lens.

I shot 40 two-minute images (80 minutes total exposure) at f/2.8 and ISO 400 and then stacked them using Siril. I also ran a star reduction algorithm to remove some of the stars so that the gas clouds would be more visible. Here are the results of that astrophotography session.

Next I would like to use a large telephoto lens to zoom in on some of these objects. Now I just need to wait for the Moon to shift into the early morning hours.