Basic Maths for Protein Crystallographers
	Resolution

The length of the reciprocal lattice vector ha^*+kb^*+lc^* is called d^* and equals .
Crystallographers often define |S|² as (d^*)² or . S, a vector, is defined as s-s₀, where s is in the direction of the scattered wave, and s₀ is in the direction of the incident wave.
Protein crystallographers talk about resolution in terms of 1/d^* (or d), hence the 'high resolution' limit is actually a small number.