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03-27-2008, 10:04 AM   #1
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K20d Dynamic Range?

Has anyone done any tests to determine the dynamic range of the K20d? Also, if so, any ideas about if the range is weighted more to the shadow areas, the highlights, or fairly evenly distributed. Talk at a Mayima Medium format site is that there is far more DR from midtones down than from midtones to highlights in Phase One backs. The solution for these shooters is to make sure that they never shoot above the 2 stops available above midtones, as they could recover the shadow areas post processing.

I am still awaiting lenses before I can shoot my own K20d.

04-06-2008, 04:29 PM   #2
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I am interested in this as well, I am curious as to what you've found out on your own or elsewhere?

Brian
04-07-2008, 04:07 AM   #3
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if you want to try take a lens, any lens.

Take one series of shots starting metered wide open, and without changing shutter speed or any other settings, take shots at successive apatures, stopping down.

Do the same thing metered stopped down, and then take another series of shots as you open up the lens.

Measure the grey scale in any photo editor, at the point where you metered (note a block wall works best) and look at the difference as you either opened up or stopped down the lens.

You will see the greyscale change for each apature.

I did this on the K10D and found that with contrast set to minimum (using JPEG) there were 6 F stops between grey scale of 25 and grey scale of 230. the top and bottom 25 in greyscale had an additional 1 1/2 to 2 stops each, compressed into that range, first stop was about 18 greyscale and second was about 7 greyscale. nothing beyond that as it was either too light or too dark (grey scale of 255 or 0 respectively)

in the middle each F-Stop was a grey scale of 40.

the long and short of it was 6 stops of full detail, one stop either side with reduced but acceptible detail, and one stop each side with minimal detail.
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