Subtractive Lighting
Posted on 26 January 2010
Today’s photography blog post is painfully obvious to pro shooters and some readers might think of this information as beginner basics. And I guess it is. If you’re a pro shooter and you’ve got a good command of light-shaping tools, feel free to skip this post. We’ll see you tomorrow.
On the other hand, I know that many of my readers are hobbyists and might just appreciate my little revelation.
I remember a few years ago at a photography show I bought my first 5-in-1 reflector/diffuser. No big deal and it seemed pretty obvious what all the surfaces were for. It’s the standard setup for a 36″ diameter disk, with a zip-on sleeve that’s silver on one side and gold on the other. And when you turn the outer sleeve inside out, it has white and black. And the center disk itself is white diffusion material. (Like this 40″ reflector by Westcott).
Based on the colors, I thought I understood what their intent was. Silver reflects sunlight or flash, very bright, without changing its color. Gold warms the color of the reflected light. The white side bounces the flash or sun, but tones it down just a bit compared to the hotter reflection of the silver side. The inner diffusion material could be used to create an “artificial cloud” softening and spreading light that might be just a bit too harsh on your subject. And the black is used as a complete light blocker or “gobo.”
While all of that is true, I was watching a class on Kelby training over the weekend, taught by one of the real masters of explaining photographic lighting, and a personal friend, James Schmelzer. He did the coolest thing with a black disk, and his example pointed out exactly what was going on.
James had a model under a covered walkway on a cloudy day. As most people know, cloudy days cause a great deal of soft, scattered light and it seems to come from almost everywhere. So the problem shooting his model was that the light coming from everywhere caused the model’s face to be almost completely evenly lit, and that caused it to look “flat.” The face lacked depth and definition. A reflector would be pointless because there was no strong, directional source of light he could capture and reflect onto the model’s face. But rather than use a flash on one side of her face to brighten it, he brought in a black disk on one side of her face and bang! That side of her face was in shadow. It’s not just that the disk was blocking some direct stream of light from getting to that side of her face (like a gobo), the black was absorbing the light on that side of the model and all of a sudden, her face had dimension. He was using subtractive lighting.
So it may be obvious to you, but so often (in fact, almost all the time) I have seen portrait lighting setups, they always talk about lighting one side of the subject’s face and then, if the other side is too dark, bounce a little light back to the other side. This was the fist time I had ever seen an environment where there was already plenty of natural light coming from every direction, and the solution was to subtract some of the light from one side.
It’s so obvious. It makes so much sense. Nevertheless, it was news to me and I can’t wait to try it. - Very cool! - Thanks James!!
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1 Response to Subtractive Lighting
Thats funny I just watched the same video last week and thought the same thing. I guess I got so into adding light I never gave a thought to when I needed to take it away. It’s cloudy alot here in the Midwest right now and this would be a good technique for me to try out.