LDR Calibration ?

I am planning to build a lumenmeter but I am not getting how to calibirate the LDR and do not have any lumen meter so if could tell the estimate lumens out of a 5w CFL or any other device might help

A "lumen meter" needs an integrating sphere, which would be an interesting exercise for a 13 year old to make.

A LUX meter you could sort of create with an LDR.
rickharris4 years ago
The LDR won't be linear so you will need a reference right through the range to calibrate it.
...or stable with temperature.