Hi guys, how do you check the calibration of your test equipment, I just check my neon screwdriver by comparing it with a known source I use 15 watt, 40 watt, and 100 watt lamps for Dim, Fairly bright and Bright also 3 compact fluorescent for White, Warm white and Daylight I have mounted the lampholders on a length of floorboard and control each lampholder via a surface mounted lightswitch Will this be ok for my Napit assessment as I believe they ask about calibration, perhaps it is better to send it off for callibration ?