ISO Stop calculations are wrong.

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Your way of measuring ISO stop differences are off. It seems your calculations are done by: (A/B)/2.

For example comparing the Nikon D3s and Canon 1Ds mk iii, with max ISO's of 102,400 and 3,200 respectively, you say that the D3s is 16 stops better. In reality the difference between the two are only 5 stops (3,200-6,400-12,800-25,600-51,200-102,400).