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dynamic range increase with RAW[]

After reading this page which describes how you can test the dynamic range of your camera, I did a quick&dirty test with my A610 and found this at the lowest ISO setting:

  • RAW: 10.3 stops
  • Jpeg: 9 stops (highlights blown sooner than RAW, shadows are the same)
  • Jpeg with 'neutral' color setting: 9.3 stops

So RAW shooting seems to give about 1 more stop of dynamic range, at least with my cam.

To do this test, I printed a sheet of paper with white, grey and black as proposed in the article. Then I took multiple photos and looked

a) which the first photo was where you can barely see all three colors (after boosting contrast) and
b) which the last photo was where you can barely see all three colors. Then I counted the stops between these two pictures.
Keep in mind that this is a test for the maximum dynamic range. The usable DR will be lower.

Here is another DR test method. Doing this test gives me 7.66 stops of DR (jpeg, normal, ISO 50).
To do this test, I shot a white wall with 1/3 stop exposure steps. Then I used the zebra indicator to find the first and the last picture without blown highlights or shadows. I counted the steps in between: 23 steps / 3 = 7.66 stops.

RAW examples?[]

I'd expect RAW samples to have a couple samples--literally. Does anybody have some CRWs for this article? 76.27.229.48 00:40, 22 April 2008 (UTC)

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