I have a t12 4' 40w daylight 3 of them 6500k 2325 Lumens. My question is when I hold a light meter (cheap one) against the bulb it reads 200 if I hold it right up to a CFL 23w it reads over 1k what gives? is that a normal reading are the Lumens cumulative? meaning because the 23w is compact the meter is reading all of the lumen output where on the 40w I can only get a small sampling?