I've been frustrated over the lighting measurement situation myself for a long time. As stated, PAR meters are too expensive. But why do we need them? You don't need to know how much PAR you have, you just need to know how your lighting set up compares to someone else who does know their PAR. With the advent of LEDs, the variety of emitters and their spectra is relatively limited, and most users could probably make useful comparisons. If you have the same exact commercially produced fixture as someone else, then even better.
