rlboyce wrote:I can believe that. I did some checking up on the Rebel specifications. They are actually much more efficient than I realized, with supposedly the same efficacy as the xm-l (albeit at different currents).
Even if the best rebels maybe give slightly less light at a given power than the best Cree LEDS, I don't think the difference if practically too significant - if comparing two lights, having a subjectively 'better' beamshape for a particular use can probably wipe out small differences in actual efficiency.
Personally, given my own light, where swapping LEDS to brighter versions from the same or different manufacturer is a simple and cheap task for me to do, even when I had LEDs 20-25% brighter than the ones I was using sitting on my desk, I didn't really the much point doing the swap - given the upgrades I have done, it seems it takes something more like a >=40% brightness increase to make the effort seem worthwhile.
rlboyce wrote:I'm starting to realize that it's more to do with Sten's small size and thermal limitations than anything else. They could really put some serious emitters in there, but the Sten would fry quitckly. I guess one of its best traits is also its weakness.
Apart from photography, there's a limit to how much light is needed for a caving light (and how much a decent-sized battery can realistically support for a worthwhile time), and I think the Sten casing is enough for most practical levels of output (even if from my biased perspective I'd have to comment that variable beamshape would allow higher outputs of the kind of light someone wanted at a particular instant within given power/heatsinking limitations.