A "Wolff Net" is the means to study stereographic projections of the crystal planes. It is particularly useful in X-ray diffraction experiments. In cartography and geometry, the stereographic projection is a mapping that projects each point on a sphere onto a tangent plane along a straight line from the antipode of the point of tangency (with one exception: the center of projection, antipodal to the point of tangency, is not projected to... X-ray crystallography is a technique in crystallography in which the pattern produced by the diffraction of x-rays through the closely spaced lattice of atoms in a crystal is recorded and then analyzed to reveal the nature of that lattice. ...

As far by the usual procedure of stereographic projection, Wolff net is drawn from the reference sphere. The projection of the plane perpendicular to the diameter of projection is projected as a reference circle on the reference sphere. The planes passing through the diameter of projection and normal to the above mentioned plane are projected as a horizontal and vertical straight lines. Great circles passing through the upper and lower poles of the reference sphere are projected as the arcs on the projection plane. Latitude circles are projected as arcs in horizontal directions. All these projections are made to the degree of the accuracy required and it completes the Wolff net projection.

To find angles between various planes, stereographic projections of the sample are overlayed on a Wolff net and, by rotating the projection suitably about the center, the two poles are made to lie on a great circle projection arc from which the angle measurement can be done easily.