The Rosette Nebula, also known as NGC 2237 or Caldwell 49, is a vast spherical H II region in the Monoceros constellation. What does it mean for an astrophotographer? It’s a fantastic astrophotography target for DSLR and small telescope (or telephoto lens) owners! If you want to capture one of the visually most beautiful deep-sky astrophotography targets, this guide is for you.
Looking for more interesting astrophotography targets for beginners? Check out my free PDF eBook: 10 Easy Astrophotography Targets for Beginners. It’s free and instant-downloadable.
Rosette Nebula factsheet
|Object type||Diffuse nebula and open cluster|
|Other names||NGC 2237, Caldwell 49|
|RA (right ascension)||06h 33m 45s|
|DEC (declination)||+04° 59′ 54″|
|Size||80 × 60 arcmin|
How to find the Rosette Nebula on the night sky
The Rosette nebula is very easy to locate due to its proximity to the Orion constellation. They are both considered as winter astrophotography targets, so prepare to shoot them from late November to early March – they are not easily available outside this time range.
So, how to locate the Rosette Nebula? First, locate the Orion Nebula. There should be an orange star near to it – it’s Betelgeuse. The Orion Nebula, Betelgeuse, and the Rosette Nebula form an imaginary triangle. Look for the Rosette at the left end of it (see at the picture above).
If you are not familiar with the night sky, download a free planetary software Stellarium and play with it; it’s a fantastic app for astrophotographers and night sky enthusiasts. For iPhone and iPad owners, I have a list of best astronomy and astrophotography apps for iOS.
Photographing the Rosette Nebula with a DSLR/mirrorless camera (One-Shoot Color)
You don’t need specialized astronomy equipment to capture the Rosette nebula. Any entry-level DSLR like Canon EOS Rebel SL2 will do the job. And that feeling when you see the emerging nebula on your LCD screen for the first time ever is once in a lifetime moment (the next wow-moment is when you actually process all the data and see the final image).
More important than a camera is a telescope. Rosette is bigger than the Orion nebula, so you need a large field of view to capture it as a whole. I recommend a small APO telescope like my Sky-Watcher Evostar 72ED (view on Amazon). Other good refractors to consider are Explore Scientific ED80, William Optics Zenithstar series, and Meade 70mm Quadruplet APO.
My mobile astrophotography setup for nebulae photographing
At the time of writing this article, this is what my astrophotography setup consists of (and this is the gear I used to capture the Rosette Nebula picture at the top of this post):
|Camera||Fuji X-T20 (view on Amazon)|
|Telescope||Sky-Watcher Evostar 72ED (view on Amazon)|
|Equatorial mount||Fornax LighTrack II|
|Light pollution filter||Orion SkyGlow Imaging Filter|
|Autoguiding||Lacerta M-GEN II|
|Tripod||Manfrotto 475B Pro|
Processing the RGB data in PixInsight
My final RGB image of the Rosette Nebula at the top of this article is fully processed in PixInsight-only (OK, I added a watermark in Pixelmator, but it’s fully doable in PixInsight too – just less convenient). Steps I took in the program were:
- Creating a master flat frame from 54 flat frames
- Calibration, registration, and integration of light frames
- Background extraction and neutralization
- Color calibration
- Linear noise reduction
- Histogram stretching
- Non-linear noise reduction
- Boosting contrast, sharpness, and saturation
- Reducing star sizes
If you want to learn PixInsight, I highly recommend Warren A. Keller’s book Inside PixInsight.