How about 18V bulbs?

well if 18V suits a 5xLi-Ion combination,

how about soem 18V bulbs like the Makita/Dewalt 18V flashlight ones that are also PR based? (the makita specs 4500Lux output, but cannot know how this is measured - anyone has an experience with these bulbs? - are good enough for a new version of a ROP?).

And am I correct that aircraft voltage is 18V??????

hopefully waiting, kostas

That's the KPR180 11 watt bulb. It's only average at 18 volts.

thnaks so it is good for a ROP-like Low only, isn't it?

Well if you want more output on 5 cells the most efficient option would be one of the 12v Osram Halostar IRC bulbs. What is needed is a ~12v, 2000hr bulb that can tolerate 18-21v for about 10 hours. There are lots of bipin and MR bulbs in that category but I don't know of any PR ones (perhaps you could try one intended for a 14.4v tool light).

You can't expect anything impressive by driving an 18v incan at spec--the KPR180 should look exactly like the Makita light and nothing like an overdriven ROP low despite using nearly as much power (note the "11w" ROP low bulb actually uses ~16w when overdriven to produce a theoretical "473L" instead of 250). This inefficiency is a consequence of the design for longer lifespan and high impact resistance which are logically higher priorities for a tool light.

Even stock Surefire bulbs are made for durability and speced to ~25-30 hours so are quite a bit less efficient than our usual fragile hotwires. I'd expect a tool light bulb to be far less efficient yet than that and require much more overdrive for decent output.

bfg9000 many thnaks for setting my perspective straight.

Indeed I did know about the relationship of overdriving and bulb hours (The Philips 5761 is a good example) but being a newbie in the incan subforum I have not come to think at the proper terms distilling the facts before mouthing something...

So it never occured to me to look at the 12V ones...Back to Luxluthor's tests thread NOW!

all the best, Kostas