Processing result of Thors Helmet NGC 2359 data from the Big Amateur Telescope (B.A.T.).

Amazing cooperation between observers from the southern and high latitude northern hemisphere.

Ha, OIII and RGB data contributed to this image by the following B.A.T. Discord members ...

SpaceKadet:
Celestron C 8 Edge HD + .7 reducer + ZWO ASI 533 MM, Ha: 12h 10min, OIII: 12h 5min, RGB: 30 min per channel

R8R0:
Skywatcher 200 PDS + ZWO ASI 294 MM, Ha: 1h, OIII: 1h

T3kko:
Skywatcher Quattro 200p + QHY 268M, Ha: 1h, OIII: 1h

Ar1s:
Skywatcher 150 + ZWO ASI 183 MM Pro, Ha: 1h

MrCrazyPhysicist:
Celestron C 14 Edge HD + Starizona Hyperstar v2 + ZWO ASI 183 MM Pro, Ha: 3h 50min, OIII: 4h 28min

Notice, that from my 54° N latitude location, Thors Helmet is only visible very low in the south about 17° - 23° above the horizon. Therefore, I can image the target only for 90 min per night during the winter months. However, due to the awesome cooperation with other B.A.T. members from the northern and southern hemisphere, we could gather enough data to reveal the fainter parts of the nebula.

The Big Amateur Telescope (B.A.T.), initiated by Astrobiscuit, is a collaboration of amateur astronomers, who share their data in order to create deep, high-resolution images of Deep Sky objects and time-lapse animations of variable nebulae.

The B.A.T. needs more Ha & OIII data for Thors Helmet to improve the S/N ratio in the fainter parts of the nebula.

If you want to contribute data for this or other targets to the B.A.T. or help processing data, follow this link:

https://discord.gg/WK8qmrqcpq

Post-Processing:

PixInsight

Ha, OIII channels (linear stage):
image integration, dynamic background extraction according to this video by VisibleDark, linear fit, creation of HOO image by channel combination, Darkarchons EZ Processing Suite: EZ Softstretch

RGB channels (linear stage):
image integration, dynamic background extraction according to this video by VisibleDark, linear fit, creation of RGB image by channel combination, photometric color calibration, masked stretch

RGB processing:
Creation of star mask with StarNet2, delete RGB image

HOO processing I:
star removal with StarNet2,  remove green tint using SCNR, create range mask to protect the brightest parts of the nebula, enhance fainter nebula by histogram and curves transformation, create luminance mask, apply HDRMT with 7 layers to equalize the brighter and fainter parts of the nebula and reveal smaller details in the brighter parts, curves transformation for contrast/color saturation enhancement, invert luminance mask, darken and desaturate background with curves transformation

Sharpening of L:
enhanced luminance sharpening using this video by VisibleDark based on this tutorial on chaoticnebula.com

Topaz Denoise AI:
Remove noise from image:
Low Light Mode On
Sharpen: 0
Remove Noise: 1

PixInsight:

HOO processing II:
Add RGB stars to starless image with Pixelmath, further contrast enhancement between brighter and fainter parts of the nebula by curves transformation, final color adjustments and increase of color saturation with curves transformation