I was thinking that if some or all of the folks that get/have this meter (including myself) could post the following info, it would be very helpful to us all:
1. Make, model, type of light fixture. T5, T8, MH, combo, CF, normal floro, incandescent, etc.
2. Bulb mfg, wattage, kelvin rating if applicable.
3. Distance of fixture from the water surface.
4. PAR range at the surface.
5. PAR range at the substrate.
6. Tank dimensions.
That way each person only does a few basic measurements, one just under the surface, and one at the substrate. Then getting a small range by moving the sensor a few inches back and forth would be easy and worthwhile IMO. For those with MH, this may be worthwhile, as the tubes would have more constant readings across the length of the tank.
I thought that this would give folks a good basis for selecting lights based on PAR rather than wpg. Since we all have the same meter it will help eliminate some variations in the results.
It would not be a controlled test or anything scientific, but would give some good and quite possibly surprising info.