Grove - light sensor - Does it need to be converted to Lux/Lumens?

Using Arduino Sensors
4

..direct sunlight, bright day, is 50 000..100 000 lux (reading 800)
complete darkness is 1 lux

u've got: light=analogRead(1); // values 0.. 800

then add:
float lux = exp(float(light)/80.0); // the number 80 must be adjusted
// adjust to lux-value close to 100 000 in clear sunlight (sun in senith)