LightingBy Peter KoloniaHow to get a cool cross-processed film look on a digital shoot in the studio.Gone Green

Popular in ads, music videos, and Hollywood, the “cross processed” look is a color palette defined by undersaturated color, slightly higher-than-normal contrast, and a greenish color cast. First done through nonstandard 35mm film processing, the palette migrated to movies as the “Bleach Bypass” look. It’s been used in the Matrix trilogy, Letters from Iwo Jima, and other hits.

You can create the look using image-editing software, but I like the ease and control of doing it with lights and creative white balancing. Touchups, if necessary, can be done in postproduction. Here’s the technique:

1 Cut a 4×4-inch square of purplepink acetate (Roscolux #05, #33, #34, or #37). With the acetate gel over your lens, create (and load) a custom white balance setting. Now, under white light, your pictures will have an overall green cast.

2 Because straight green highlights look ridiculous (especially in faces), you need to confine the greenish, cross-processed look to shadows and the distant background. To achieve that for the portrait above, I filtered the main light — a snooted Elinchrom Style 1200 RX — with the same Roscolux #37 4×4-inch filter used to set the white balance. Result: Almost natural skin tones, but green everywhere else.

3 In software, reduce saturation and dial up the contrast a bit.

Bonus tip: How to light muslin.

Muslin backdrops are popular with portrait shooters. A cotton fabric named for Mosul, Iraq, muslin sheets are inexpensive, customizable (by painting over), lightweight, and easy to hang, yet heavy enough to hang relatively straight, without folds. They’re also easy to transport and store — many shooters just jam them into sacks.

This convenience, though, comes at a cost: wrinkles. Ironing these out of a 12×12-foot sheet of stiff cotton can take hours. I know.

Lighting to the rescue!

To minimize the crinkles and creases in muslin backdrops:
• Avoid side lighting which exaggerates surface texture.
• Use a continuous light source rather than strobe lights.
• With your camera on a tripod and your subject holding still, set shutter speeds of between 1 and 2 seconds.
• Use a fan (or, better, an assistant) to move the muslin during the exposure. The longer your shutter is open, the less vigorous a movement is required. Goodbye wrinkles!

Ask Peter

Q. Can you recommend DVDs on lighting?
A. For portraits, try James Schmelzer’s Indoor and Outdoor Lighting Techniques ($100, direct; 586-790-3686). For products and more, I like the four-DVD Best of Dean Collins on Lighting ($179; www.soft ware-cinema.com).