How to photograph the Trifid Nebula (M20)
A red emission nebula split by dark lanes, with a blue reflection halo.
When to shoot it from your location
About the Trifid Nebula
The Trifid has red emission, blue reflection and dark dust lanes all in one small area. Shoot it unfiltered to keep the blue, or with a dual-band filter if your sky is bright.
Gear and framing
The Trifid Nebula spans about 28′ of sky. It frames best with:
- Small refractor (250-600mm)
- Long focal length (800mm and up)
You can see how other people have built their rigs on RigDesigner, including my Sony a6700 and 60mm refractor rig.
Filters
This target glows in emission lines and also has broadband detail. Unfiltered color frames under dark skies give the most natural colors. A dual-band filter lets you shoot it from the city or with the Moon up.
Tips
- Unfiltered color frames keep the blue reflection region that narrowband filters remove.
Processing
Stack your light frames with darks and flats, then remove the background gradient before stretching. AstroBake does all of this for you. Point it at your folders of raw frames, then adjust the result with live sliders.