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Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
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Getting plate-solving status, please wait...
Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
Powered byPixInsight

Acquisition details

Dates:
April 23, 2019 ·  April 28, 2019 ·  May 7, 2019
Frames:
Astrodon Gen2 I-Series Tru-Balance Blue: 29×20(9′ 40″) (gain: 76.00) -20°C bin 1×1
Astrodon Gen2 I-Series Tru-Balance Blue: 44×30(22′) (gain: 76.00) -20°C bin 1×1
Astrodon Gen2 I-Series Tru-Balance Green: 30×20(10′) (gain: 76.00) -20°C bin 1×1
Astrodon Gen2 I-Series Tru-Balance Green: 42×30(21′) (gain: 76.00) -20°C bin 1×1
Astrodon Gen2 I-Series Tru-Balance Lum: 473×20(2h 37′ 40″) (gain: 76.00) -20°C bin 1×1
Astrodon Gen2 I-Series Tru-Balance Red: 30×20(10′) (gain: 76.00) -20°C bin 1×1
Astrodon Gen2 I-Series Tru-Balance Red: 113×30(56′ 30″) (gain: 76.00) -20°C bin 1×1
Integration:
4h 46′ 50″
Darks:
50
Flats:
25
Flat darks:
60
Avg. Moon age:
15.02 days
Avg. Moon phase:
41.36%

RA center: 12h28m44s.44

DEC center: +12°4824.10

Pixel scale: 1.620 arcsec/pixel

Orientation: 147.041 degrees

Field radius: 1.199 degrees

More info:Open 

Resolution: 4224x3238

File size: 19.6 MB

Locations: Home, Broadlands, VA, United States

Data source: Backyard

Description

This is my first mono/filtered image and is still a work in progress.

revision a: 30 minutes L and 10 each of R, G and B.

revision b&d: 93 minutes L, 10 each G and B, 40 R

revision e&f: 156 minutes L, 63 R, 31 G, 32 B

Exposures were 20s @ gain 76 and was processed with darks, flats, and flat darks. On revision B I upped the red exposures to 30s as the mean was a bit low on that channel. For E all the color channels were 30 seconds.

See the description on revision F for processing details. I really tried to keep the image from looking too processed and think I made some progress in that regard. I'd be happy to know what others think!

Comments

Revisions

  • Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
    Original
  • Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
    B
  • Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
    D
  • Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
    E
  • Final
    Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
    F
  • Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda
    G

B

Description: This adds in 63 minutes of Luminance and 30 more minutes of red. Unfortunately, an autofocus problem kept me from getting anything usable in the other channels that night.

This was processed similar to the first version except that the luminance master was stretched with HT rather than Masked Stretch. I may have taken this a bit too far with the luminance stretch and LHE.

I'm hoping to get some additional data on the next clear night and I'll be a bit gentler to try to keep the image a bit smoother. This time I was pushing to see what was really in there and the answer seems to be not all that much

Uploaded: ...

D

Description: Revision C was making my eyes bleed. I toned it down just a bit with the midtowns adjustment in HT and it doesn't seem quite so harsh now.

Uploaded: ...

E

Description: This version adds in two more hours of data (22 minutes blue, 21 minutes green, 26 minutes red and 63 minutes luminance).

Pre-processing:
drizzle (scale 1)

Post-processing:
L: Dynamic Crop, DBE, HT
R, G & B, Dynamic Crop, DBE
Combine RBG
RBG: PCC, HT
LRBG Combination (.2 saturation & chrominance noise reduction)
LHE (masking out background)
Curves (saturation, masking out background)
Curves (contrast, masking out foreground)
TGVDenoise (luminance, masking out background)

In Photoshop:
a bit of chrominance noise reduction and saturation boost in camera raw filter

Uploaded: ...

F

Description: Apparently, I just can't stop working on this image. This time I started with local normalization at scale 512 and after integration ran the mure denoise script on each file.

After that processing was pretty conventional: DC, DBE, RBG combine, PCC, HT Stretch on RBG and L, LRBGCombination (saturation at .2 and chrominance noise reduction at defaults), LHE (42, 1.5, 0.5) on larger structures, and finally curves for some contrast and saturation.

Uploaded: ...

G

Description: This is an annotated version showing the Messier, IC+NGC, PGC and quasar catalogs. To my surprise there are 8 (maybe 9) smudges that might really be quasars in here!

Uploaded: ...

Sky plot

Sky plot

Histogram

Markarian’s Chain & Messier 87 (LRGB), 



    
        

            Linda