How Much Exposure from a Reflector to Fill at Sunset?

[Walter Lowe]

Hey all,

I'm coming up on a project where I'm dealing with a lighting challenge and the project is ultra-low budget for a non-profit, so I don't have a big team to drawn on. We're shooting a group of individuals together in the middle of a field near sunset. My vision for the shot and the way the location works best is to put the setting sun behind and slightly off to the side of the talent and fill them in with bounce. I'd love to have a few HMIs out there to fill, but the location is too remote, and doesn't really work for big lights and a generator.

I've done this plenty of times when it's just a medium shot or MCU of a single person and you can get a white bounce in nice and close. That's no problem, but for this shot it's a group, I need to fill a larger area and the reflectors would need to be further back. Is there a formula or rule of thumb to estimate how large a reflector surface I'll need to provide a certain number of stops of fill? I need to know if a couple of 8x8s will do it, or will I need more and bigger, or if it just isn't possible and I'll need to scrap or re-imagine the shot.

Any thoughts would be appreciated.

Edited September 21, 2016 by Walter Lowe

[David Mullen ASC]

Better to under-fill than over-fill -- if the sunset light is a little hazy, the contrast won't be too high anyway, and the worst case scenario is shooting directly into a bright sunset sky with a clear overhead sky, and having to silhouette the foreground to hold the colors at the horizon, and in that case, you'd need a ton of fill to compensate and it would look rather artificial.

 

So I think some large bounces will be fine, I'd even probably use Day Blue instead of white in order to not warm up the shadows so much.

[Miguel Angel]

Another thing that you might want to try is bringing a couple of 1 meter x 1 meter mirrors and use them as fill through those frames (this time with difussion) you are going to take with you.

 

Plenty of power using just the sun and no need for HMIs or generators.

 

Have a good day.

[JD Hartman]

Reflector boards are available as well as mirror boards.

https://www.bhphotovideo.com/c/product/32737-REG/Matthews_119732_Reflector_42x42.html

 

You can rent them.

[Tyler Purcell]

Yea, those reflector boards with diffusion work wonders. :)

[Walter Lowe]

Thanks Gentlemen. Sounds like either a couple 8-bys with for bounce or maybe some 8-by frames with diffusion and some reflector boards to focus some sunlight into them will work then? I appreciate the knowledge.