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Sensor positioning

Positioning sensors correctly relative to the render model allows you to adjust the mapping of the signal on the surface. There are five types of adjustments: an "y-offset" which acts in along the anterior-posterior dimension, a "z-offset" which operates along the "inferior-superior" dimension, an "x-rotation" along the left-right dimension, a "theta-scaling" which is similar to the z-offset but keeps theta angle proportions constant and the x-stretch, which can compensate for the flat sides of the realistic head model as compared to the sphere mode which is used for spherical spline interpolation .  These transformation are configured on the "positioning" page in the VIEWAVERAGE section of the configure-study dialog. Similar controls are available in the mapper context menu.

The effects of the transformations are illustrated below:

Y-Offset and Z-Offset transformations are spherical projections on a translated model as shown in the following graph, sensor distances are not proportionally transformed.