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2013: NGC 4565; Needle Galaxy in Coma Berenices
Image details
Date: April 1, and 2, 2013
Exposure: 7 hours 10 min (43x 10 min), ISO800, 30 Darks, 50 Bias, and 41 Flats

Telescope: 8" Skywatcher Newton
@F/5 with MPCC 
Mount: NEQ6-pro, controled by EQmod/CdC, guided by  QHY5/9x50 Finder Guider/PHD
Camera: Peltier-cooled Canon 350Da 
Location: Emmen, The Netherlands

High resolution: (2,22 Mb)
DSLR-LLRGB post-processing workflow  according to Scott Rosen's video tutorial:
Original RGB image in Photoshop CS3/Nebulosity 2.5:
 -Gradient Exterminator
 -DDP (Neb 2.5)
 -Auto Color Balance (Neb 2.5)
 -Correct artifacts with spot heal brush
 -Levels [Black-, Grey-, and White points]
 -Convert to greyscale [This creates the Synthetic Luminance]
 -Convert back to RGB [RGB reconvertion is only done for easy of interpretation of PS histgram and tools]
Synthetic Luminance in Photoshop CS3:
 -Curves, selective on weak dustlanes, with anchored background and highlights, 2x normal curve
 -Levels correction for background blackpoint
 -High pass filtering (40px & 8px; Don Goldman method)
 -Carboni's v1.6 Deep Space Noise Reduction [Removes noise from background, not DSO]
RGB processing in Photoshop CS3:
 -Curves and Levels to bring RGB to a comparable level as the Luminance
 -HLVG, medium strength
 -Carboni's v1.6 Space Noise Reduction
 -Carboni's v1.6 Less Crunchy, More Fuzzy
 -Increase saturation using Adam Block's method [3 copies of RGB, 3rd copy Luminosty blend mode, 2nd copy soft light blend mode, flatten all 3 copies] Repeat to taste, 11x for this image. This results in a slightly over saturated image
 -Selective color, reds, yellows, blues
 -Luminance addition on 100% opacity, Luminosity blend mode [The general idea is to increase the saturation of the RGB stepwise, until the luminance can be added at 100% opacity]

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