In the full size original the piece of white card (behind the doormat) shows some clipping in the bottom right corner but checking with the eye-dropper tool shows RGB values less than 250 for all but the extreme bottom right. The exposure was 1/200; f/11;ISO 100 - about 2/3 of a stop below the camera recommended figure.
The blue carpet on the stairs has a small pattern which is useful for this exercise.
The metered figures from around the scene are given in this picture (all at f/11, with 0.7 EV underexposure dialled in as per the original shot). This is clearer in the full size image.
The reading on on the white card is 1/1000 sec. Just above the envelope on the stairs is a black shoulder bag (on the second stair) which records a reading of 1/3 sec. The stair pattern is clearly visible without too much noise interference. By the seventh stair (1.3 sec – approx 2 stops darker) the pattern is lost in the noise, so the bottom end of usability is around 2/3 sec giving a practical dynamic range that runs from about 1/1000 to 0.6 seconds – around 9 stops – which compares reasonably well with the lab figures on DP Review a well known (and respected) source of digital camera reviews
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