E-M5 has DR 13!

Started Apr 13, 2012 | Discussions thread
Detail Man
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Re: Clarification about how Digital Camera DR and SNR are specified
In reply to Timur Born, Apr 14, 2012

Timur Born wrote:

Detail Man wrote:

In the case of a digital camera, (the maximum) SNR is measured by taking the ratio of the image-sensor system's maximum (so deemed linear, perhaps ambitiously, by somebody ... ;)) output signal when illuminated divided by the RMS (vector-summed) value of the sum of all noise-sources (Read Noise, Dark Noise, Photon Shot Noise, etc.). As a result of the existence (almost entirely) of Photon Shot Noise in that situation, the SNR is indeed smaller in value than the DR (as can be seen in DxOMark's RAW-level test-results). I write this in order to amend my misguiding of the readers ...

In practice, how much lower is SNR to be expected compared to DR? At DxO the Fujifilm X10 is measured at 10.98 EV dynamic range with a SNR of 37.4 dB (100% gray at ISO 100), the GH2 is only measured 10.82 EV dr with a SNR of 39.1 dB (100% gray at ISO 160). And that's a comparison of 2/3" (X10) vs. mFT (GH2) sensor.

At full illumination, the "state of the art" seems to top-out in the range of 40 dB (a linear factor of 100:1, around 6.6 EV, bits, or "stops"). bobn2 would be the best person to ask on that stuff.

The Dynamic Range is probably most associated with reductions in Read Noise. Again, ask bobn2 . He has a very thorough understanding of the various tecnological characteristics/factors involved.

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