The Rosette Nebula (NGC2237) is an emission nebulae in the constellation of Monoceres not far away from the bright star Betelgeuse in the constellation of Orion. It cloud of hydrogen gas is illuminated by the young star cluster NGC 2244 at its center. Stellar winds from these stars energize the surrounding gas, causing it to glow strongly in hydrogen-alpha light (pinkish/red in the image).
The image above, like most of the ones on this site, was captured using long-exposure astrophotography techniques, combining multiple stacked exposures to increase signal and reduce noise. Dithering was also used to further reduce noise and enhance the image quality. Dithering is the process of shifting the mount by a few pixels in a random direction between exposures.
This image was taken on March 11 and March 21, 2026 using a RedCat51 with a dual narrowband L-Enhance filter on March 11 and with a broadband IR/Cut filter on March 23. The image is composed of stacked forty-seven (47) 180 second exposure images taken at two sites in Florida; Palm Beach Gardens (narrowband) and at Pine Glades (broadband) over about a 5 hours total on the two nights. Guiding was done using a 120mm guide scope, and PHD2 software. The mount used was a ZWO AM3 strain wave harmonic mount. NINA was used for imaging acquisition running on a Mele 3Q PC. The stars are relatively pinpoint and round since tracking was good and the ZWO electronic auto focuser kept tight focus throughout the imaging session.
Image was processed in Siril, including background extraction, color calibration, and hyperbolic stretch. Also performed a Starnet star removal and recombination in Siril. Final image processing and Nik Dfine noise reduction done in DXO Photolab.
The stars in the image are just from the broadband session and because they are done in broadband you can see the true star colors, ranging from blueish to golden/yellow. The nebula part of the image is from the combined
Haven’t imaged this target since March of 2023, details an image from that session are below.
The above image was taken on March 6, 2023 using the OpenAstroTracker with OpenAstro Guider and Auto Polar Alignment. Camera used was a ZWO ASI533MC Pro and an Lenhance Filter. Scope was a f/2.0 135mm Focal Length camera lens. Image acquisition done using Ekos and Kstars running on a Rapsberry Pi. Guiding done using PHD2.
Stacked a total of 31 180 sec images in Siril. Also performed gradient correction, color calibration, and stretching in Siril. Final touch ups performed in Gimp.