Photographic Dynamic Range (PDR) is a More Useful Measure than the DxOMark Landscape Score

Started Apr 17, 2015 | Discussions thread
OP bclaff Veteran Member • Posts: 8,680
Re: Photographic Dynamic Range (PDR) is a More Useful Measure than the DxOMark Landscape Score

Detail Man wrote:

bclaff wrote:

Detail Man wrote:

bclaff wrote:

So in DN, which is what we have in the raw data, the E-M5 read noise is 1.07 DN and the GH2 read noise is 2.08 DN for engineering dynamic ranges of 11.9 and 10.9 respectively.

Interesting. I and another person were coming up with Std Devs on the order of 0.8 for the E-M5, and 1.0 for the GH2 (at base ISO on each; 200 and 160, respectively) using RawDigger. Truly ...

I can't speak for anyone else.
The 1.07 and 2.08 figures are computed from the sensorgen data for consistency in our discussion. My values from DxOMark data are 1.173 and 2.083; pretty close to those at sensorgen.

So it seems that you are scaling the Read Noises by the ratio of the image-sensor FWCs, then ?

Again, chicken versus egg (Bill says: egg came before chicken, gain came before FWC).

FWC = (max DN) * gain
and
e- = DN * gain

So yes, I got the gain value by dividing the FWC by max DN.
And then I got DN by dividing e- by gain.

Naturally e-/FWC and DN/(max DN) match.

Regards,

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