Here are some graphs that we put together using a spectrometer.
Here is the spectrometer we used, an OceanOptics S2000.
I have about 28 total graphs, half of which is really good for reef keepers so I won't post them here, but you can see them in my photobucket account here:
Or at nano-reef.com here:
Some info on testing I am editing this post to include.
Distance from the LED to the radiometer sensor was 12" in all of these cases; the sensor was not moved and the LEDs all used the exact same mounting bracket to hold them steady. I build 3 small wooden holders to hold them steady on their temporary heatsinks (1/2" thick, 1" square acrylic/Corian bricks with doublesided FastCap SpeedTape).
No secondary optics were used in any of the graphs listed above. Only 1 graph that has not yet been posted used optics, and it is a comparison of "with/without" optics on a Rebel 3-up. I am awaiting further data for this one.
Cree XPG and XPE LEDs, Bridgelux LEDs, and Rebel LEDs: Primary optic angle 120 degrees.
Cree XRE- 90 degrees.
Satistronics 3w, 10w, and 20w emitters: 140 degrees.
Here are the graphs we got for LED combinations I think will be useful for us.
Note this: I am fairly confident that ANY of the white LEDs in the graphs below will grow plants just fine so make your selection based on what you think will look good. Don't frustrate yourself over picking the right color.
----- that is, unless you are trying to get them to bloom or seed or something else that requires manipulation of color temp.
COMBINATIONS OF WHITES OR WHITE/BLUE