Celestial hemisphere:  Northern  ·  Constellation: Cassiopeia (Cas)  ·  Contains:  Bubble Nebula  ·  LBN 548  ·  LBN 549  ·  LDN 1231  ·  NGC 7635  ·  Sh2-162
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Bubble Nebula (HSO), 



    
        

            Linda
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Getting plate-solving status, please wait...
Bubble Nebula (HSO), 



    
        

            Linda
Powered byPixInsight

Acquisition details

Dates:
July 1, 2021 ·  July 2, 2021 ·  July 3, 2021 ·  July 4, 2021 ·  July 5, 2021 ·  July 6, 2021 ·  July 7, 2021 ·  July 8, 2021 ·  July 9, 2021 ·  July 10, 2021 ·  July 11, 2021 ·  July 12, 2021
Frames:
Astrodon H-alpha 5nm: 33×900(8h 15′) -20°C bin 1×1
Astrodon OIII 5nm: 39×900(9h 45′) -20°C bin 1×1
Astrodon SII 5nm: 41×900(10h 15′) -20°C bin 1×1
Integration:
28h 15′
Darks:
40
Flats:
48
Bias:
40
Avg. Moon age:
19.40 days
Avg. Moon phase:
17.13%

RA center: 23h20m43s.138

DEC center: +61°0907.72

Pixel scale: 0.727 arcsec/pixel

Orientation: -87.944 degrees (flipped)

Field radius: 0.545 degrees

WCS transformation: thin plate spline

More info:Open 

Resolution: 3846x3781

File size: 1.9 MB

Data source: Own remote observatory

Remote source: Sierra Remote Observatories

Description

I'm in the midst of a reprocessing spree and I redid the bubble with the same tone mapping technique I've been using on recent narrowband images. Along the way I flipped the palette over to HSO as the SOH tended to leave a lot of hot pink on the screen and it was a bit much visually.

Here's the processing outline:
H, S and O masters:
dynamic crop
deconvolution
starXterminator (generating stars)
histogram transformation
tgv denoise
channel combination in lum
pixel math in stars using a star mask

HSO:
channel combination (HSO)
hisotogram transformation to line up peaks
pull out a lum for later processing

lum:
tgv denoise
lhe (2 scales)
MLT sharpening

stars
channel combination (HSO stars)
histogram transformation

In photoshop I fixed a couple of artifacts that were caused by the way were operating the camera then. We've since corrected our procedure but it had left a blob near the bubble that shouldn't have been there so thanks to PS context aware fill it is no longer there.

--------------------------------- original processing -------------------------
The Bubble Nebula, NGC 7635 is a HII region where the stellar wind from a hot star how blow out a gas free region around it.

Processing:

the H, O and S masters:
dynamic crop
MLT noise reduction
deconvolution
linear fit (on O and S to H)
channel combination (SOH)

on the SOH:

SCNR on a large greenish star halo
TGV Denoise
HT stretch
curves (contrast & color desaturation)
Adam block's star reduction
adv sharpening

I ended up doing something on this I've never done before and that was actually desaturating the color slightly. This helped the purple gas stand out a bit more from the background while still keeping it appearing diffuse.

Comments

Revisions

  • Bubble Nebula (HSO), 



    
        

            Linda
    Original
  • Final
    Bubble Nebula (HSO), 



    
        

            Linda
    B

B

Description: Redid with tone mapping. See main text for details.

Uploaded: ...

Sky plot

Sky plot

Histogram

Bubble Nebula (HSO), 



    
        

            Linda