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01-24-2011, 11:06 AM - 1 Like   #31
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A/C flicker, 1/3 stop differences, etc., it all does not make sense in my 'test' situation. As Wiker remarks: why then only at 160-200 AND only when D-range turned on?

I also do not see too much difference in global exposure between the two shots. To demonstrate this here are details from the original pictures (Left=160 ISO, Right=200 ISO):

For me, the upper two details are nearly identical in exposure, the lower detail isn't. That just doesn't match with 1/3 stop theories etc...

01-25-2011, 02:29 AM   #32
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QuoteOriginally posted by boomklever Quote
AND only when D-range turned on?
D-Range shoots by 1EV less ISO value than what you set (i.e. if you set ISO200 then actually the camera will take the picture at ISO100) and then brightens up the image by whatever amount the cam thinks is best.
So when you select ISO160 with D-Range ON then the camera actually takes the shot at ISO80 and during processing the image data it brightens the image - I can imagine that due to whatever reasons related to using ISO80 instead of ISO100 some highlights gets clipped during this process. Don't forget that ISO80 is in the extended ISO range, on paper ISO100 is the standard base ISO value.
01-25-2011, 04:36 PM   #33

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QuoteOriginally posted by Wiker Quote
This is a public forum where the level of expertise and knowledge varies greatly. Might be a challenge for experts to bear with the novices, but it would be a much better forum if experts (or is it "experts" ?) could explain things properly, instead of just putting things off as ridiculous.
Actually, it was all explained satisfactorily within the very first page, among the very first replies. And the proper explanations were ignored in favour of crazy conspiracy theories by people who can't help but see sinister things in the simplest phenomena.

Those are some great "high morals" you have there.
01-25-2011, 07:13 PM   #34
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Hi, Boomklever,
Did you replicate this issue, say with 5 shots in succession on same setting, then say, again with the 2 settings, 5 shots each, in natural light?
I have inconsistency on old camera indooors, trying various things, and I am looking to update, so interested in your results.
I see an uncivil one is interfering with yr thread, -shame.

01-26-2011, 05:43 PM   #35
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I think this is a relevant field of research. I too would like to know why highlights are being more severely blown in ISO 160 than 200 when 160 should theoretically have more dynamic range.

Sorry Boomklever that your thread has been mangled so terribly. I hope you find your answers.

Simico is correct in his/her explanation of D-range operation.

You say that the results are much more consistent (no anomalies) with D-range turned off. This makes me think there actually may be something not quite right in the algorithm.

I don't think D-range has been adequately explored on the K-5 yet, so i'm glad someone has taken the time to check it out. Rep added.

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