Celestial hemisphere:  Northern  ·  Constellation: Canes Venatici (CVn)  ·  Contains:  IC 4277  ·  IC 4278  ·  M 51  ·  NGC 5194  ·  NGC 5195  ·  Whirlpool Galaxy
Getting plate-solving status, please wait...
Messier 51 (HaLRGB), 



    
        

            Linda
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Getting plate-solving status, please wait...
Messier 51 (HaLRGB), 



    
        

            Linda
Powered byPixInsight

Acquisition details

Dates:
June 24, 2021 ·  June 25, 2021 ·  June 26, 2021 ·  June 27, 2021 ·  June 29, 2021 ·  June 30, 2021 ·  July 1, 2021 ·  July 2, 2021 ·  July 3, 2021 ·  July 4, 2021 ·  July 5, 2021 ·  July 6, 2021 ·  July 7, 2021 ·  July 10, 2021 ·  July 11, 2021 ·  July 12, 2021
Frames:
Astrodon Gen2 I-Series Tru-Balance Blue: 22×480(2h 56′) -20°C bin 2×2
Astrodon Gen2 I-Series Tru-Balance Green: 17×480(2h 16′) -20°C bin 2×2
Astrodon Gen2 I-Series Tru-Balance Lum: 34×900(8h 30′) -20°C bin 1×1
Astrodon Gen2 I-Series Tru-Balance Red: 31×480(4h 8′) -20°C bin 2×2
Astrodon H-alpha 5nm: 14×900(3h 30′) -20°C bin 1×1
Integration:
21h 20′
Darks:
40
Flats:
37
Bias:
40
Avg. Moon age:
17.56 days
Avg. Moon phase:
45.30%

RA center: 13h29m50s.415

DEC center: +47°1252.17

Pixel scale: 0.728 arcsec/pixel

Orientation: 91.303 degrees (flipped)

Field radius: 0.308 degrees

WCS transformation: thin plate spline

More info:Open 

Resolution: 2356x1932

File size: 142.7 KB

Data source: Own remote observatory

Remote source: Sierra Remote Observatories

Description

M51, the Whirlpool Galaxy -- one of the best places in the night sky to see gravity in action!

This was taken with the telescope at SRO where I'm an imaging team member.

Here are the steps for revision D:

RGB:
channel combination
dynamic crop
DBE
SPCC
blurXtermnator
noiseXterminator
cloned after this step for separate star stretch
starXterminator
GHS (GHS, linear, GHS)
noiseXterminator
LRGBCombination in L
extracted R channel for continuum subtraction
NRGBCombination in H
curves (contrast & slight color removal)
pixel math in rgb_stars (screen)

L:
channel combination
dynamic crop
DBE
blurXtermnator
noiseXterminator
cloned after this step for separate star stretch
starXterminator
GHS (GHS, linear, GHS)
HDRMT (masked)
LHE (masked)
MLT (very mild sharpening)

H:
dynamic crop
blurXtermnator
noiseXterminator
starXterminator
GHS (GHS, linear, GHS)
pixel math (H - 0.7(extracted_R - med(extracted_R))

rgb_clone
GHS stretching for stars
starXterminator

l_clone
GHS stretching for stars
starXterminator

rgb_stars
lrgbcombination in l_stars


The steps below are the original processing:

Processing steps:

Lum
dynamic crop
MLT (noise reduction)
deconvolution
make two copies, lum_l and lum_h

lum_l
HT stretch to bring out detail in the body of the galaxies

lum_h
HT stretch to bring out the "haze" around the galaxies

lum_stretched
pixel math average lum_h and lum_l
HDRMultiscaleTransform
LHE
ha
dynamic crop
MLT (noise reduction)
deconvolution
HT stretch

red, green and blue
dynamic crop
MLT (noise reduction)

RGB
channel combination (red, green, blue)
HT stretch
LRGBCombination with lum_stretched
NBRGBCombination with ha
Curves (color)
Adam Block's star de-emphasis
AdvSharpening
TGVDenoise

Overall I was very happy with the result here!

Comments

Revisions

  • Messier 51 (HaLRGB), 



    
        

            Linda
    Original
  • Messier 51 (HaLRGB), 



    
        

            Linda
    C
  • Messier 51 (HaLRGB), 



    
        

            Linda
    D
  • Final
    Messier 51 (HaLRGB), 



    
        

            Linda
    E

C

Description: The inverted image shows that the arcs of stars extend well below M51 and its companion. The arc is so faint that it doesn't really show up against the black background but the inverted image makes it stand out a bit more.

Uploaded: ...

D

Title: Revisited after one more years of learning

Description: Sometimes it is instructive to go back to old data to see if the limits on the original version were the data or the processor. In this case I think it's safe to say the new tools (GHS & the Xterminators) combined with more knowledge at my end combined to get more out of the data.

Uploaded: ...

E

Description: bit of extra cropping

Uploaded: ...

Sky plot

Sky plot

Histogram

Messier 51 (HaLRGB), 



    
        

            Linda