From the ElumTools website:
ElumTools New Features
These features are included in the latest releases of ElumTools 2018, 2017, and 2016.
Isolines and Spatial Maps
ElumTools now has two new tools to help you evaluate the gradient of light across a workplane or surface: Isolines and Spatial Maps. Isolines are contour lines drawn through values of equal illuminance and Spatial Maps are partially transparent shaded color plots showing similar gradients. You can use the two tools independently or…
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