the little conversions you do forty times a day.
dec = round(% × 255 ÷ 100) · 1 fc = 10.764 lx · 1 ft = 0.3048 m.
three conversions in one panel: dmx level as percent, decimal 0-255 and hex; footcandles to lux; feet to meters. every field is live in both directions, so you work from whatever number the console, the meter or the drawing happens to be speaking in.
decimal = round(% × 255 ÷ 100), 1 fc = 10.764 lx, 1 ft = 0.3048 m. half a dmx channel is 128, not 127 — a preset reading 127 is somebody's rounding convention, not a fault.
the hex column earns its keep. reading a dmx packet in a monitor, or typing raw values into rgb channels, checking FF against 100% here beats trusting the arithmetic you did at 1am.