Light settings change the light calculations when displaying 3d
objects. Material and light properties are multiplied to determine
the final light value. Ambient light is non-directed light affecting
every point of each object and can be thought of as self illumination
of the head model. Diffuse light/material carry the displayed signal in
EMEGS (Qt version) and therefore are determined by the loaded dataset.
Specular light/material produces bright reflections that are highly
dependend on the angle between view point, surface normal and light
source. Specular and ambient parameters can be configured on the lights page in the VIEWAVERAGE section of the configure-study dialog or in the mapper window context menu.
Below are examples of the effect of the 3 light and material
components on the plot output.