How to light low fog in an old warehouse (music video)

[Torben Greve]

Hi...

 

Basically this my first thread. Been exploiting your forums for a while since they are a pretty good resource of anything cinematic :)

 

But here's a question I couldn't find the answer to through searching.

 

There are some threads about fog and such, but I'll be shooting a video on tuesday where the production wants to add low dry ice fog in some shots.

The premise is a pretty large room in an old warehouse. There are angled steel columns in the middle and around 10 meters of space on each side.

 

This room will be a general shot in the video, and also marks the scene where 8 meter warm colored explosions will appear behind the artists.

 

So far I'm counting on stop 8 to avoid overexposure of the explosion, therefore I've settled on 2.5K HMI 8 meters away at 1/120s for key light (camera is native 500 iso, Sony FS100), but this is where the low fog comes in...

 

Can I get away with backlighting the low fog with 1.2K HMIs on flood or do I need to sacrifice one of the 2.5K on that as well? I was hoping to use the other 2.5K for enhancing the depth of the room by lighting the columns. Or maybe I should just use the 2.5K so it works with both the fog and the columns?

 

I'm up for any ideas at all...

 

The lights I have available for this job is:

2 x 2.5K HMI Daylight fresnel

2 x 1.2K HMI Daylight fresnel

2 x 800w tungsten

 

Camera settings:

stop: 8

exposure: 1/120s

iso: 500

FPS: 50p (needed for a general slow mo mood throughout the video)

 

 

Thanks!

[Matt Read]

It really comes down to how big the room is and how you want to light dry ice fog.

 

If you just want to illuminate the fog so you can see it, then depending on the size of the room your 1.2ks should work fine as a back light. Slap them up on some stands and you're good to go.

 

If you want to put the light below the level of the fog so that it diffuses the light and the fog becomes a source of its own, then I don't think a two 1.2ks will do the trick. They're too hard of sources to evenly illuminate all the fog from below. Something more like a bunch of bare Kino tubes would work better. However, maybe having beams of light through the fog would be interesting, in which case your 1.2ks would be just fine.

[Torben Greve]

By chance, the low fog wasn't available, so we rented the smoke instead and I think that really did the trick for the video.

 

I'd like to share with you the end result of what I asked in my initial question.

 

Lighting was done with 1.2K and 2.5K Arri HMIs. The keylight in the walking shots down the smokey hall were done with an Arrilite 850w only filtered with some white diffuser.

The explosions were shot with F8 on the FS100 at 1/120s and 50FPS.

 

It was a fun job, hope I can work on some more like this, since this was my first real lighting job.

 

http://www.youtube.com/watch?v=Lfg4DIzxMnQ

[Matt Read]

Looks good, Torben. You could have fooled me on this being your first lighting job.

[Torben Greve]

Looks good, Torben. You could have fooled me on this being your first lighting job.

 

Thank you... well, in all honesty, it was my first video lighting job. But being a commercial still photographer, I made the assumption that I could more or less directly translate the way I light from shooting with flash to shooting with video. I did try to read up a little in the Set Lighting Techs handbook and used the Arri calculator. I'm glad I did... the production team wanted to rent 650w to begin with before I stepped in and demanded 1.2K hehe.

 

Having seen it a couple of times myself now, I can't really tell if I should have used a key light with the same temperature as the HMIs instead? I keep telling myself "It's supposed to look like the fluorescents in the ceiling...", but then again, maybe it would have looked more pleasing with a divalite or something.