5,000 light years away from our planet, an open cluster of young and bright suns excite nearby atoms to produce this flowery nebula, the Rosette Nebula.
I collected about 5 hours of Hydrogen-α (Ha), Oxygen (OIII) and Sulfur (SII) using my light-pollution fighting setup from my light polluted garden, using dedicated scientific narrowband filters and an astro-monochromatic CMOS sensor constantly cooled at -15C.
I calibrated the frames, stacked them and star-aligned them using Star Alignment. Then, I used Pixel Math algorithms to process the data with a specific pattern that NASA is using to produce the stunning photos from the data they gather from the space Hubble telescope, Hubble palette, SHO (stands for Sulfur II, Hydrogen-α and Oxygen III).
I spent 3 hours fine-tuning the algorithm, performing a series of pixel-level arithmetic and logical operations between images and suddenly I got the perfect result. Then, I applied noise reduction with ACDNR that stands for Adaptive Contrast-Driven Noise Reduction, a highly flexible implementation of a novel noise reduction algorithm. I also used Automatic Background Extractor, Histogram Transformation, auto-stretched it with STF (Screen Transfer Function) and improved the contrast and saturation with Curves Transformations.
In the end, I applied some final touches with Photoshop including a Selective Sharpen method with the High Pass Filters, which worked really well.
26th & 27th February, 25th, 28th March 2019, Bedworth, GMT+0, United Kingdom, Bortle Class 5 ~SGM: 19.57 mag./arc sec2
Camera: ZWO ASI 1600MM-PRO USB 3.0 Mono (Type CMOS)
Sensor Cooling Temperature: -15C
Filters: 1.25" 5nm Astrodon Ha, 1.25" 3nm Astrodon OIII, 1.25" 3nm Astrodon SII
Imaging Telescope: Takahashi FS-60CB
Correcting Lens: Takahashi Reducer 0.72x (composite focal length at 264mm and focal ratio at f/4.9)
Mount: iOptron CEM25EC
12Bit ADC (FITS)
50 x 180" Ha subs (Unity Gain, Gain: 139, Offset: 21, Binning 1x1)
42 x 180" OIII subs (Unity Gain, Gain: 139, Offset: 21, Binning 1x1)
42 x 180" SII subs (Unity Gain, Gain: 139, Offset: 21, Binning 1x1)
20 Darks, 20 Flats
PixInsight 1.8 Core