NGC 3576 Extracted-Emission-Line Image (Alex Woronow)

NGC 3576 Extracted-Emission-Line Image

NGC 3576 Extracted-Emission-Line Image

OTA:……………….TAO 150 (f/7.3)
Camera:………….FLI - ML16200 (1.13 arcsec/pixel)
Observatory:….Deep Sky West, Chile

EXPOSURES:

EXPOSURES:
…R: 10 x 900 sec.
…B: 28 x 300
…G: 12 x 300
…O: 11 x 1800
…H: 13 x 1800
…S: 17 x 1800
Total exposure   25.6 hours

Image Width: 1.4 degs
Processed by Alex Woronow (2022) using PixInsight, Topaz, Photon, SWT

This image uses extracted emission-line data. That is SHO that is emission-line only, excluding the continuum in the narrowband images. The method for this extraction is of my own making, and an explanation of an early version can be found on the PI forum. Basically, the methods form a pair of simultaneous equations describing the emission line and continuum components in the R,G,B and H,S,O images. This method of obtaining the emission lines is fundamentally different from the method Vicent Peris’s Continuum-Subtraction method and can be applied to SII and OIII as well as Ha data.

The extracted lines were then mapped to their approximate true colors (or as close as I can get to the true colors), and photometrically color-calibrated in PixInsight. A little additional color enhancement, in PI, Topaz, and Photon produced this image.

Aside 1: Contact me with a personal email and I will gladly send the script. But beware it is a Beta-stage script. I am working on testing it further and documenting its use.

Aside 2: Peris (here) says that the Continuum-Subtraction method assumes a uniform intensity of the broadband R across the entire image. That criterion seldom exists. My method makes no such assumption and uses a pixel-by-pixel separation of narrowband-line intensities from the continuum.

Final
Original
B

B

Title: AI HDR version

Description: Hit with the Lemur (Photolemur) and blended back with about 60% of the original image

Uploaded: ...

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Status	Advanced success
Started	...
Astrometry.net job	5911206
PixInsight job	50AZCQJ0AUAADY3H6Q53CON403CZXZY8
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	11h13m04s.60
RA (top/left)	11h08m50s.21
RA (top/right)	11h19m56s.57
RA (bottom/right)	11h17m30s.78
RA (bottom/left)	11h06m01s.79

Dec (center)	-61°18′49″.8
Dec (top/left)	-60°34′17″.8
Dec (top/right)	-60°57′25″.9
Dec (bottom/right)	-62°02′50″.8
Dec (bottom/left)	-61°38′55″.7

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