using big sources....when you never have before

[Adrian Correia]

Most of my shoots involve smaller units with 1.2K and 2.5K HMIs and 2K tungstens usually being the biggest units. My question is...how do you know what larger units to use if you don't really have the opportunity to use them? I mean...how do you discern wheather a 5K would be enough or you really need something bigger. There is a feature I am shooting in April where this could be a concern....I know I could rely on my gaffer but you know the deal...always looking to better myself. Thanks guys!

[David Mullen ASC]

The short answer is experience -- you know if using a 5K regularly when it's not quite enough, so next time you might try a 10K.

 

It doesn't take long shooting for a couple of days to learn how much light output to expect from the units in different conditions. Maybe the first time you use an 6K HMI PAR, you find it's way too much light for that set-up, so the next time you try a 2.5K HMI PAR instead.

[Daniel Madsen]

So photometric data would never serve you in a situation like this?

[David Mullen ASC]

So photometric data would never serve you in a situation like this?

 

I haven't taken much time to study the data. The only situation I would think it would be useful is comparing different units of the same wattage, or if I had to put a big light on a condor that was 500' away and wanted a good idea of how many footcandles I'd get out of it.

 

But the truth is often that you get the biggest light you can afford and work with it -- "oh, I guess the 18K across the lake is not quite bright enough to get an f/2.0 here... well, spot it in halfway...OK, that works..." or "poop, that Dino three blocks away is only giving me an f/1.4... well, break out the Super-Speed lenses, guys...too bad production wouldn't let me rent two Dinos..."