Kuma5 is a 4 circle X-ray diffractom calculator for 2D detectors.

The file Kuma5 you can download from the File galleries for 64 bit version of windows.

You kan freely rotate(left mouse button) and zoom (right mouse button) the reciprocal space in left window. Right window shows the view from the 2D detector. It is simply part of the Evald sphere.
This calculator is for kappa geometry diffractometers. Right now it can calculate orientation matrix for two reflections with set of angles. Additionally I added the angles to hkl calculator. In setting window you can change the uit cell parameters wave lenght, detector distance and orientation matrix. From left window it is possible to see how the crystal is oriented in respect to the labolatory coordinates. In right window on the top the numbers shows hkl indices for position on the detector. In future I planing to add corections for Lorens and polarisation coeficients.