How to photograph the Omega Centauri (NGC 5139)
The largest and brightest globular cluster, with about ten million stars.
Photo byESO(CC BY 4.0)
When to shoot it from your location
About the Omega Centauri
Omega Centauri is a huge ball of stars, likely the core of a dwarf galaxy swallowed by the Milky Way. It is easy from the Southern Hemisphere and low on the horizon from the southern United States.
Gear and framing
The Omega Centauri spans about 36′ of sky. It frames best with:
- Telephoto (85-300mm lens)
- Small refractor (250-600mm)
You can see how other people have built their rigs on RigDesigner, including my Sony a6700 and 60mm refractor rig.
Filters
This is a broadband target, which means its light is mostly starlight across the whole spectrum. Shoot it with no filter or a UV/IR cut filter. A broadband light pollution filter can help a little in the suburbs. Dual-band and narrowband filters block most of its light, so leave them off. Plan it for a moonless night at a dark site.
Tips
- It is bright and handles moonlight well, so it is a good target for short sessions with the Moon up.
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.