What is the perpendicular (smallest) Fresnel reflection value for water?

The IOR is 1.33. The smallest reflection value is given by ((I-1) / (I+1))^2.

For water then, it is (.33 / 2.33) ^ 2  = .02.

Now render me a flat black surface with 2% reflection, showing something like a figure, with and without Gamma = 2.2. Tell me which one is horribly wrong and why.

Now make that surface also 10% diffuse white. Render again with and without gamma = 2.2 and tell me which is horribly wrong and why.

Then do 50% diffuse white. Surprise - not so horribly wrong anymore. Why? Because it's the darks that are more wrong than the lighter things, unles you use GC=2.2. Why do Poser users add light? Why do they boost colors? Because they look horribly wrong otherwise.

For those who want the answer, the one without GC=2.2 is horribly wrong. The reflection in the black surface will be almost or completely invisible - not at all like water.

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