Author Topic: Colour control - single, bias calibrated, debayered, dslr_raw images  (Read 8291 times)

Offline georg.viehoever

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Re: Colour control - single, bias calibrated, debayered, dslr_raw images
« Reply #15 on: 2010 December 08 11:41:13 »
Hi,
I did a quick run on your image based on the CR2 file (00006.CR2) that you provided.

- load with default RAW settings (bilinear interpolation, no blackpoint correction, everything else unselected)
- Fast rotation counter-clockwise (just to get things correctly oriented, should have no influence on color)
- BackgroundNeutralization. As reference area I chose a dark region in the trees in the background
- ColorCalibration. White reference was the white card in the foreground
- ScreenTransferFunction for a little bit more contrast.

The exact settings and regions are visible in the attached screenshot. I am quite happy with the result.
Would you like to do something different, or where is the problem?

Georg
 
Georg (6 inch Newton, unmodified Canon EOS40D+80D, unguided EQ5 mount)

astropixel

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Re: Colour control - single, bias calibrated, debayered, dslr_raw images
« Reply #16 on: 2010 December 08 13:05:25 »
Hi Georg. Thanks. That's very close. The area that suffers most is restoring the yellow tones. This is particularly evident in the greenery. It's not stark green, but has softer yellow tones. Otherwise the blues and reds are very close.

Now that I've narrowed the issues down, I'm interested in learning how to restore the yellow undertones.

Offline georg.viehoever

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Re: Colour control - single, bias calibrated, debayered, dslr_raw images
« Reply #17 on: 2010 December 08 13:27:26 »
Playing a little bit with STF (moving blue slider a bit to the left, and red slider slightly to the right), I was able to produce a color impression that is almost identical to what I see in Canon's DPP. See screenshot.

If you are interested in emphasising certain colors, I would try the ColorSaturation Tool.

Have fun with PI!

Georg
Georg (6 inch Newton, unmodified Canon EOS40D+80D, unguided EQ5 mount)

astropixel

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Re: Colour control - single, bias calibrated, debayered, dslr_raw images
« Reply #18 on: 2010 December 08 13:45:12 »
Thanks Georg. That is very close to the original. Well done.
As I narrow the issues down, the main contributor is dslr_raw format settings. The colour renders better with alternative settings to that used for astro shots - including defining the default RGBWorkingSpace seems to be the best approach.
« Last Edit: 2010 December 09 01:23:53 by astropixel »