Green and Blue for B&W

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I've been known to use colored gels on more than a few occasions when shooting pretty girls. Often enough, I've utilized Rosco's Bastard Amber or Straw to warm the skin of more than a few sexy models. The two other gel colors I've often employed are CTB (Color Temperature Blue) and CTG. The latter being -- Yeah. You Guessed it. -- Color Temperature Green.

Green and blue aren't gels used to warm skin. (People aren't Smurfs or green-skinned alien creatures, after all.) But they can be used effectively in glamour and nude photography in a variety of ways. One such way is with images intended for B&W conversion.

How so? Well, since human skin doesn't include blue or green in its skin tones, the green and blue in an image can be easily manipulated without effecting the skin tones. One such manipulation where using green or blue gels can come in handy is when you're converting to B&W.

In the image above from a set I snapped a while back, I was shooting with model Faye in a small apartment against a bare wall. The wall was texture-coated and painted off-white. I used two lights: a main light set camera-right about head-high and modified with a medium-sized, shoot-through umbrella, plus a bare-bulb strobe on the floor behind her, angled almost straight up. I metered my main light for a good exposure but cranked up the back light to create a very hard and obvious edge around her and to back-light the smoke so it would be well portrayed in the image. I also gelled the back light with CTB for some of the captures.

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The image on the right is the SOOC (Straight Out of Camera) capture for the photo above. (Re-sized, not cropped, for the web.) The blue-gelled back light has its own "cool value," in my opinion, and also affords me the ability to manipulate it in post -- manipulate it quite a bit, in fact -- when converting to B&W.

Because there's no blue to the model's skin tones (or her scant wardrobe for that matter) I was able to easily adjust the levels of the background in post by simply choosing the color blue as my "key" for such adjustments.  For the image above, I brought the tone of the blue way down, i.e., darkened it quite a bit, in order to further "pop" the model from the background and to add some interesting value to the bare wall. I was also better able to accentuate the texture of the wall working in B&W.

Manipulating the blue for a B&W conversion isn't the only thing I could do with that blue. Since the blue isn't part of the model's skin tone, I could manipulate the blue in various other ways for color versions of the image. I could have done the same thing with a green gel as green isn't present in skin tones either. That's why, of course, when they're producing many special effects for motion pictures, they utilize "green screen" and "blue screen" backgrounds because it allows the film-makers the ability to "key in" other things while not effecting the images of the actors or other subjects, props, foreground sets, etc. that don't contain the colors green or blue, whichever they chose for their background key.

I'm a big proponent of experimenting, not on my clients' dimes but when I'm shooting for myself. You might want to try introducing green or blue gels into you pretty girl shooting or for almost any portrait work that's captured against a seamless, neutral background, especially if you intend to convert those portraits to B&W.  I don't suggest you first try doing so if you're hired to shoot portraits for a client or customer but, once you've gotten comfortable using such gels and techniques, you might want to sometimes work into you productions workflows, including your paid-work workflows.

Model Faye, seen in the images above, is someone I've worked with a fair number of times. I've shot her in "just for fun" pics, as well as commercial glamour, tease, and also some fashion work for an LA clothing designer. As a teen, Faye was an American Apparel model and, combined with her subsequent volume of glam and tease work, it's all helped make her a very experienced model: Easy to shoot with (user friendly, as I sometimes like to say), easy on the eyes, and a model who knows how to very effectively "work" her side of the camera. The image I used for this update was captured with an 85mm prime lens on a Canon 5D1, ISO 100, f/6.3 at 100th.