Okay, so I picked up the PAR meter today and did some readings around my tank and plotted the results with GnuPlot.
The Y is front to back measurement (inches), and X is left to right measurement (inches):
The par heatmap for the surface of the tank is next to useless. You can REALLY see the impact of the LED lenses.
At the surface of my rock pile, the story is a bit more interesting (note the rescale of the heat map -- colors were very washed out otherwise):
Finally, midway between the top of the rock pile and the bottom; note the void where the rock scape is:
Finally, a few other measurements:
- Rock "island" on sand bed, left side of tank: 60
- Lowest ledge on rockscape where a coral could be, left side of tank: 180
- Lowest ledge on rockscape where a coral could be, right side of tank: 120
Its interesting to observe that at the top of the rock pile, the light is still quite concentrated.
At the top of the rock pile, I have a usable area with a PAR around 350-500. I think the LED optics are too tight as I still see a bit too much variation for my liking.