X-E1 & X-Pro1 Dynamic Range

What is useful to think about is maximizing exposure.

When the exposure is optimized the imathe e rendered from data with the best possible signal-to-noise ratio, SNR, and dynamic range. In data recording nothing beats SNR, and high SNR also means dynamic range is not wasted on bits used to digitize noise. Instead of ETR, think about how to record more photons (signal) and less noise.

There are  the three basic steps to maximize exposure.

First, select the aperture to obtain the depth-of-field required for the photograph you envision.

Next, select a shutter speed that freezes either camera and, or subject  motion as needed. Electronic stabilization or a tripod provide more shutter speed flexibility.

Finally, fine tune either aperture or shutter speed to retain only the interesting or important highlights in all three channels. This means some highlights may intentionally be overexposed.

ISO is not directly relevant to maximising exposure because exposure depends only on aperture and shutter speed. But ISO does affect the flexibility in selecting aperture and shutter parameters used to achieve the best possible SNR (exposure). This is why SNR performance at high ISO is important. It turns out for CMOS sensors raising the ISO (to a point) improves the shadow SNR, once the first twos steps are decided. At the same time the higher ISO can make the last step difficult to achieve.

This is really not ETR, instead it is deliberately maximizing the data's SNR. The resulting exposure will often resemble a ETR histogram, but the similarity ends there.

I first learned the maximize exposure strategy by reading posts from Prof. Emil Martinec. The theory and empirical data for the physics that support his approach are described in the following technical article:

http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/