Regulation Advice Needed

I'm building either a 2C or 3C light. It will be employed in rural India, owned by an 80 year old, and will only be able to be powered by C cell primaries.
the emitter is a K2 U00 on a hotlips.


1.Durability/reiability
2.Brightness
3.Battery life


3C DD K2
3C Resistor regulated DD K2
3C (no idea what type?) regulated converter K2

2C Badboy K2

Not the answer you want but,

I'd get a Lambda SMJLED PR2 bulb (or a few) and pop them in a C cell host such as the Duracell Multi (light, flash button and candle mode) or a 2C Mag. See comparison below.





You'd get good runtime, 200mA draw gives 40+ hours.Its reliable, stock parts are cheap and if the host goes then another can be found locally. If its a rural environment, from other posts, I think most suggestions were for dimmer lights rather than blasters.

You could send a PR2 bulb and host ahead, whilst you ponder the regulation problem.

Cheers.

Rural India you said... and for use with primaries only...

for the 2C I would recommend the MadMax+ driver
for the 3C the Wiz2 would be a good choice.

BTW where in India will this light go on duty...