not strictly led - but i dont really know where to ask....

i have a homemade floodlight that i use for filming skateboarding
its a camera tripod with 2 mr16 flood type bulbs (diachoric - sp)
the bulbs are 12v 50w and they are run off a 12ah lead acid battery (so not overvolted - therefore a bit yellow)

basicly i want to know how many cree or ssc stars (just the dx ones) it would take to equal or improve the amount of light (with suitable reflectors for a similar flood) running the stars at say 750 - 1000ma.

cooling would be ok as this is at night outside and stars can be attached to a big sheet of copper or something

any help is greatly apriciated