Lighting controller including control system having first control facility and second control facility. First and second control facilities respectively are for controlling first and second visible-light sources including first and second pluralities of semiconductor light-emitting devices spaced apart from and along longitudinal axis. First and second visible-light sources respectively are positioned for directing first and second beams of first and second visible-light emissions from first and second pluralities of semiconductor light-emitting devices in first and second beam directions. First and second control facilities respectively are programmed for controlling first and second intensities of first and second beams of first and second visible-light emissions. Control system is programmed for modulating first intensity of first beam and second intensity of second beam in manner for causing first and second beams of first and second visible-light emissions to collectively emulate progression of ambient sunlight. Lighting systems and lighting control methods.