IC 2118 – Witch Head Nebula
The Witch Head Nebula is a faint reflection nebula in the constellation Orion. Its appearance resembles the side profile of a Witch face, complete with a long nose and pointy chin! The dusty areas of this nebula are lit by the nearby star Rigel. Cataloged as IC 2118, this nebula is believed to be an ancient supernova remnant.
It’s a dim astrophotography target for those shooting with a DSLR camera and telescope, and it’s also quite large. To fit the entire nebula complex in a single frame, a camera lens with a focal length of 200mm or more is needed.
My photo was taken using a telescope with a focal length of 480mm, and a 0.8X Reducer:
The Witch Head Nebula – 18 x 5 Minute Subs
My image of the Witch Head Nebula captures most of this dusty blue lady, using an Explore Scientific ED80 APO refractor. The images were captured at a dark sky site, with much less light pollution than at home. The full photo details of this target are listed further down the page.
IC 2118 – The Witch Head Nebula
My image is a heavy crop, framed up to show the “Witch Head”. I have rotated the image to show the iconic shape this nebula is famous for.
The toughest part about imaging this subject is confirming that your target is in the center of the frame. This nebula is so faint that you may not even see it in your test images until you bring it into photoshop and adjust the curves. I have created a graphic below to illustrate just how faint this reflection nebula really is.
How to locate and frame your deep-sky target under light-polluted skies
In the early stages of your Astro-imaging session, bring your first long exposure image into Adobe Photoshop to confirm that the faint details of the deep sky object are well framed. By performing a quick levels and curves adjustment, you will be able to see a preview of what your final image will end up like.
You must have a copy of Adobe Photoshop installed on your field laptop of course. I use an old version (CS3) that I keep installed on that machine for that exact purpose. This is especially helpful when photographing a dim object from a light-polluted area, as it will be hard to pick the subject out of the heavy pink sky.
The telescope used for my photo – Explore Scientific ED80
A quick check of your data the field
Using the eyedropper tool, set the grey point on your image to separate the DSO from the sky. Follow-up with a quick levels adjustment – slide the left-hand slider in towards the data on the histogram. You should start to see some of the faint details of your subject at this point. You can also perform a quick curves adjustment to pull the details out even further.
Chances are, this single frame will now how a horrible gradient around the edges, and be a noisy mess. The purpose of this quick test is just to make sure you have framed up the object properly. Make any adjustments to your framing based on your preview.
IC 2118: Photo Details:
Photographed on: February 19, 2014
Telescope: Explore Scientific ED80 with WO Flat III 0.8x FR/FF
Mount: Sky-watcher HEQ-5 Pro
Guiding: Meade DSI Pro II and PHD Guiding
Guide Scope: Orion Mini 50mm
Camera: Canon EOS 450D (Stock)
Total Exposure: 1 Hour, 30 Minutes (18 x 5-minute frames)
Processing Software: Deep Sky Stacker, Photoshop CC
Support Files: 15 dark frames
Guided with PHD Guiding
Stacked in Deep Sky Stacker
Processed in Adobe Photoshop CC
I have not attempted IC 2118 since early 2014, on my Sky-Watcher HEQ5 Pro mount and 80mm refractor. I am tempted to try this deep sky object again using my 105mm Canon Lens on the iOptron SkyTracker Pro. At this focal length, I should be able to include the Orion Nebula in the same frame.