On the determination of fiber tilt angles in fiber diffraction

The common digital method that is used to eliminate the effect of fiber tilt from fiber diffraction patterns is based on an approximation given by Franklin & Gosling [Acta Cryst. (1953), 6, 678-685]. The estimate of the tilt angle is iteratively optimized in the so-called `Fraser correction'. Building on the fundamental work of Polanyi [Z. Phys. (1921), 7, 149-180], the exact solution is presented.