I've been going through Hank, Simon, and Lumintop's multi-emitter lights a lot lately. One thing that bugs me is the heat vs output balance. I tend to wonder if one maintains a greater lumens per degree than the other within the same chassis/frame, 3 or 4 emitters? Has there been a study on this that I can eyeball?
If we could get perhaps a Lumintop FW3A or KR4 using the same emitters and measure temps and lumens along a few dedicated points in the temp range, then take the same chassis/frame and install a 4 emitter setup in it and do the same, that would be perfect. The FW3A is a great light as is the KR4, and Hank's boost driver seems to be a good design, so perhaps we can find an ultimate setup that uses both, and the most efficient setup being either 3 or 4 emitters to achieve the same results.
With a regulated driver more LEDs always means higher efficiency except at low current where the efficiency of an LED decreases..
With a FET driver, not sure.
Edit : nevermind I missed the part you mentionned efficiency in relation to throw.
So, let's say we have a reflector that provides an equal spill and hotspot for each emitter count, is there a point in current output where 3 is as efficient as 4 emitters since we're jamming 4 emitters in the same space?
4 emitters are more efficient than 3 at the same current, you get more lumens per watt. The resulting luminance of the surface - cundella - depends on the optic.
Perhaps, but is there not a point where the emitter is now at a fixed output, but the surrounding heat is causing inefficiency? My point is being made specifically towards a scenario where either 3 or 4 emitters are in the same exact chassis. So, less cooling space between them, and around them. So, you're disspipating more of that current in heat than in light?