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 R/THETA RE-BINNING

R/THETA RE-BINNING transforms a 2-D Cartesian coordinate system pixel image into a polar coordinate system pixel image. There is arbitrary choice of the number of radial and angular pixels.

Spatial distortion, beam centre, and detector tilt are taken into account. The command TILT/CENTRE BEAM (see Section 17.26, Page [*]) can be used to determine the tilt and optionally the beam centre. If a semi-transparent beam-stop is used the beam centre can be found be fitting a suitable function e.g. 2-D Gaussian (see Section 17, Page [*]). Other commands may also be useful e.g. the PIXEL X/Y option within the DISPLAY sub-menu of the graphics menu of the IMAGE command (see Section 3.5, Page [*]).

By varying the number of radial and angular bins this command allows anything from a 1-D radial profile, to a 1-D azimuthal profile of a diffraction ring, to a number of radial profiles as a function of angle, to be produced.



Andrew Hammersley
2004-01-09