Amprobe lm 100 light meter manual ranging amprobe lm 100 the amprobe lm 100 light meter measures the visible light from fluorescent metal halide high pressure sodium or incandescent sources it is a portable easy to use digital light meter designed for simple one hand operation reading in lumen lux or foot candle fc units the lm 100 measures a wide range of light up to 20 000fc or lux with an accurate high resolution of 0 01fc lux br br br use the lm 100 light meter to measure t