Substractive lighting - fashion photography -black booth technique - Peter Lindbergh & Steven Meisel
I think maybe you're reading a little too much into the setups. I'd bet the primary purpose is to keep their subjects out of the direct sunlight. Keeps the models more comfortable and avoids the harsh contrast sunlight can create. Yes they could have used white tenting which may have created a softer light overall around the subjects. But I'm not sure the images would have looked all that different and the choice for black is probably to keep the subject cool as much as anything else.
Perhaps stating the obvious, the reason I use black is to reduce reflected light. This is helpful to build contrast. For instance, I do a lot of product photography and often the edges of my subject might otherwise blend in with the background. So I use black cards on either side to reduce reflected light and build contrast.
Likewise, when doing portraits, on a person's face, it could have a slimming effect by creating a steeper gradient of light across the face (makes the face look thinner - try it). So it's not to say there aren't uses for "subtractive lighting". And when I do headshots for models/actors, a common technique is to look for a darkened doorway/alcove when the light comes primary from the front and quickly falls off - this is what your black tent also does. But that's usually when I'm not using strobes and want to maximize available light.
But in your case, the choice of black and use of a "tent" may have been more practical than artistic. Do either of the actual photographers discuss this anywhere?
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