Is this a painting or a photograph? In this classic celestial still life composed with a cosmic brush, dusty nebula NGC 2170, also known as the Angel Nebula, shines near the image center. Reflecting the light of nearby hot stars, NGC 2170 is joined by other bluish reflection nebulae, a red emission region, many dark absorption nebulae, and a backdrop of colorful stars. Like the common household items that still life painters often choose for their subjects, the clouds of gas, dust, and hot stars featured here are also commonly found in this setting — a massive, star-forming molecular cloud in the constellation of the Unicorn (Monoceros). The giant molecular cloud, Mon R2, is impressively close, estimated to be only 2,400 light-years or so away. At that distance, this canvas would be over 60 light-years across.
Given the amount of clouds that have been and will be plaguing my location in the coming months, I’ve decided to start experimenting the some telescope live data. It’s and interesting blend of high and low quality – the images are taken from extremely low bortle zones with amazing telescopes, but there are usually strange artifacts, gradients, and bad star quality.
Image:
You can access the full quality PNG here: https://live.staticflickr.com/65535/52698155016_a1ce08fef8_o.png
Details:
Telescope: ASA 500N Chi-2
Camera: FLI PL16803
Filters: Astrodon LRGB Gen2
Location: Telescope Live's El Sauce Observatory, Chile
Date of Observations: 3/24/2022, 3/25/2022,, 3/26/2022
L: 6 x 600s
R: 6 x 600s
G: 6 x 600s
B: 6 x 600s
Processing: Pixinsight
Credits: Data: Telescope Live; Processing: William OstlingProcessing:
Pre-processing and Stacking
- Linear defects from the CCD were removed using pixinisight's lineardefectdetection and lineardefectremoval script
- The subframes were weighted and registered in WBPP
- the RGB channels were individually integrated and drizzled
- The L channel was integrated with the RGB channels to create a master L
- L,R,G,B were drizzled
Preparation of all frames:
- Stacking artifacts were cropped
- RGB Channels were combined to create an RGB image
- RGB image was plate solved
- Starless DBE was applied to L, RGB as follows:
- Starnet 2 was applied to a clone of the target image, creating an image with stars and an image without stars
- DBE was applied on the starless image to create a background model
- The background model was subtracted from the stars image
- the RGB image was photometrically color calibrated and clipped H values were fixed with the repaired HSV separation script
Deconvolution of the luminance
- a PSF was created using the dynamic PSF process
- Linear starnet was applied to create a starless image and a star mask
- the linear image was duplicated, stretched, clipped, and convoluted to create a mask
- The starless image was deconvoluted using the RVC algorithm
- the stars were added back in
Linear noise reduction
- A low contrast mask was created and applied
- Noise Xterminator was applied with strength 73 and detail 0
Stretching
- The luminance image was stretched using GHS targeting RGB
- The RGB image was stretched targeting Color and RGB
Non-linear adjustments
- The nebulae was enhanced using the starless enhancement method
- Large scale structures were enhanced using MMT and curves
- HDR multiscale transform was applied
- Large scale structures were enhanced using MMT and curves
- Large scale structures were iteratively enhanced using MLT, LHE and curves
- The star sizes were reduced following adam block's method
- Curves and Histogram transformation
- Dark structure enhance
- Slight non-linear noise reduction using ACDNR