Exposing for fire

[Tom Banks]

I came across a question this summer while shooting an action feature in which we had a EXT NIGHT scene where a man was lit on fire from some exploding gas cans behind him. I wasn't sure how exactly to expose for fire, if it would read at any f-stop or if it would blow out at a certain point. But I had to light the location and expose for the two at the same time. I ended up just pushing my lights in as close as the FX guys said was safe to get the most punch out of them and try to get the location to read closer to how bright the fire would read.

 

Has anyone had any experience with this or could offer any rule of thumb? Also something I wasn't sure was if the quantity or quality (type of explosion) would determine how bright the actual flame got.

[Kevin Zanit]

Fire can be over exposed like anything else, the more over you go, the less orange/ red the fire appears.

 

For good colored fire, figure you need to expose it at a 5.6/ 8 split on 500asa leaning towards the 8.

[David Mullen ASC]

In practical terms, it basically means you light the scene to the highest level you can, which is generally not that high for a night exterior. "Terminator 2" lit their night scenes to a T/5.6 for the scene where the building explodes.

 

You do the best you can. If you can get away with it, when the fire gets bigger, you can stop down the lens more, being aware that the background will then go darker in comparison.