Runtime for HD45 5W?

I've looked at the HD45 FAQ thread but did not see a runtime graph for the 5W HD45... Anyone know the High/Low runtimes for the XX1T HD45?

Going by the math, and assuming equal driver efficiency; I'm estimating about one hour and fifteen minutes if driven at 750 ma on High.

Here is my reasoning, using the runtime data for the 3w:

~3.6v to the LED x .950 amp x 1.86 hours runtime = ~6.36 Watt/hours

This is the ~ amount of power getting to the LED
Assuming the drivers are equally efficient I'll do the math:

6.36 watt/hours / .750 amp / 6.6 volts to the LuxV = ~1.28 hours

So That's where I'm getting my 1:15 estimate.

I don't know what voltage is going to the Lux III version to get 18 hours of runtime on low. It would almost have to be less than the ~3.6 volt rating because using that number, I'm getting 9.72 watt/hours power to the LED. If we were to use that number to figure runtime for the LuxV:

9.72 W/H / .15 A / 6.6 volts to the LED = ~ 9 hr 45 min. on low

I know we're talking apples and oranges here but this is my best effort to estimate runtimes.

Thanks for the estimate... However, did Don actually do a runtime test on the 5W?

Not yet I think ... which is the reason why you don't find it in the FAQ
Unfortunately I can't do those nice graphs as I don't have a lightmeter with an automated data-logger.
However ... if anyone has got a graph I'd be most happy to put it in the FAQ asap.
bernie

P.S.: I'd "guesstimate" more about 1h than 1:15 to be on the safe side ... and depending on Vf of the LED, of course