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Old 25-04-2010, 10:10 PM
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dugnsuz (Doug)
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IC2944 processing comparison

Hello all...
A wee while back I asked how others how they processed their Ha images taken on DSLRs. Some said they converted the combined image to greyscale, others said they split the combined RGB into its component channels, kept the Red one and discarded the others.
I wanted to see which method provided the best result.

Data was 9x15min subs, 300mm lens, f4 @ iso1600, Astronomik EOS clip-in Ha 12nm filter

Left hand image: RGB image stretched in Levels then converted to Greyscale.

Middle image: RGB image split into component channels, Red channel kept and stretched in Levels.

Last image: a layered blend of the 2 (75/25)

Obviously the Channel split image on the right is brighter, but it looks like a fair bit of subtle detail is blasted out - seems a layered blend of the 2 images might yield the best result (or a more aggresive stretch of the Greyscale converted image!?).
It looks to me like there should be a sweet spot between the 2 images.

All comments appreciated
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Last edited by dugnsuz; 26-04-2010 at 10:17 AM.
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Old 25-04-2010, 10:24 PM
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h0ughy (David)
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personally i think your first method is better - the other is over saturated - you wont be able to recover the fine detail in the bright overexposed areas
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Old 25-04-2010, 10:52 PM
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dugnsuz (Doug)
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Quote:
Originally Posted by h0ughy View Post
personally i think your first method is better - the other is over saturated - you wont be able to recover the fine detail in the bright overexposed areas
Thanks David - the latter processing route is the one I've used for other projects. But it was for the reasons you state that I thought I'd try this out.
Perhaps some objects need a more subtle processing approach than others!?
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Old 25-04-2010, 11:13 PM
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strongmanmike (Michael)
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Ah huh! The whole chicken!

Yep proecessing can vary from object to object. The first probably looks the best

Mike
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Old 25-04-2010, 11:21 PM
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dugnsuz (Doug)
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Originally Posted by strongmanmike View Post
Ah huh! The whole chicken!

Mike
...and nothing but the chicken!!

I'm afraid I like it big,bold and brassy! So No.2 pulls me toward it!
I still think the middle ground exists - ??stretching up from the left hand image?? As Houghy said, you cant come back from an over saturated image.
Doug
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Old 25-04-2010, 11:29 PM
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dugnsuz (Doug)
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Put yer money where your mouth is!
Here's a blend of the 2 images 75% Left with 25% Right.
Added to OP...
Doug
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Old 26-04-2010, 03:53 AM
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Baptista (Baptista)
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Hi Doug

Great job! As usual! Your photos are very pretty!

Cheers
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