Light for Night Work: Task Illuminance Bounds and a Shared Work-Bench Design That Bounds Added Hours Without Inventing Productivity

A $59 shared bench light delivers 584.4 lux at centre and bounds 3.5 usable added hours per evening (875 h per seat per year), while failing tailoring dark cloth at its 750 lux upper bound and falling to about 104.6 lux at the bench ends. Fine manual work at night - net mending, sorting, tailoring, harvest processing - is done under light far below what the tasks require.