One additional note: What should I do if the terrain I'm shooting on is flat? i.e. I have no way to get the HMI's more than 15-20 feet off the ground (with the tallest stands)?
Even with powerful HMI's like 6k or 12k wouldn't that cause real problems with light intensity and beam diameter for wide shots covering a lot of area? For example, if i had several 6k's on 11 foot crank stands at 60 feet off, wouldn't the intensity of the light range a whole lot from close to the light to farther off, and also, it would emulate a sun very low in the sky, correct (and thus casting long shadows)?
Again, not very versed in this stuff, so any help would be huge.