Illuminations: Get Creative with Cookies!

by Jim Stinson
March 2005

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When you light a set or location, you're not just cranking out lumens to get a good f-stop. You're painting the scene with light, and a powerful painting tool in your kit is the cookie. Cookies are big cards with patterns carved out of them and placed in front of lights to throw shadows on walls and other surfaces. (If you care where the odd name "cookie" comes from, consult the adjacent sidebar -- though it won't help very much.) Cookies are easy to make and use, and they're more fun than a barrel of people, so let's see what they can do for you.

Cookies are large (at least 24" square) cards or boards -- sort of like big lighting flags with patterns cut out of them. By placing them between a spotlight and its target, you can throw distinct silhouettes like leaves or window blinds. You can create tinted patterns by fronting any cookie with a colored gel. Cookies are typically made of metal, cardboard, or, as we'll recommend, thin plywood or foamcore board. As we'll also see, we can often use some dimensional objects as cookies.

What Cookies Do At their simplest, cookies can spruce up a dull surface by varying the light washed across it. This is useful for the background walls often visible during interviews with talking heads. It can also add snap to a plain gray curtain backing a studio set.

Many special-purpose cookies work great for softening the background. By placing them quite close to their lights, their silhouette shadows are too soft to reveal any pattern. Instead, they produce a subtly variegated wash across the background. If you need a dedicated wall-breaker-upper, a design like Figure 1 works well if you make the holes small and irregular, and place the cookie close to its light source. For location lighting, strong color washes can look hokey, but you can slip a light blue or amber gel over the spotlight behind the cookie to cool or warm a bland background.

Cookies often suggest things that are outside the frame (remember: if it's not in the frame, you can imply that it exists). Very common patterns include Venetian blinds (Figure 2 -- we'll explain why the blind cutout is raked) or the mullions of bare, small-paned windows. Leaves or leafless tree branches (Figure 3) are also common. Incidentally, the all-purpose mottled cookie shown in Figure 1 also works well for leaves when you place it farther away from its light source, to create more distinct shadows.

When suggesting off-screen objects with cookies, you can often strengthen the effect with colored gels. For example, a pale green gel used with a leaf cookie can help sell the illusion that the scene is in a sunlit forest.

Home-Baked Cookies

Though you can cut cookies out of sheet metal or cardboard, you'll find that plywood and foamcore board are easier to work with.

For quick and simple construction, use a sheet of half-inch foamcore board -- the kind with rigid Styrofoam sandwiched between sheets of paper. Choose a board that's black on both sides, to control bounce from the light source. Look for boards two feet square or larger. The bigger the board, the farther away from the light it can be placed and the bigger (and simpler) the cuts you'll need to make to create a pattern.

Now, draw the silhouette you want on the board. I like to use a classic Xacto knife, but any matte knife or box cutter will serve. Cut against a throw-away board so that you can make deep knife passes that slice cleanly through the foamcore.

Remember: the light will shine through the holes, so the part you don't cut will throw the shadow. This sounds obvious, but I once got confused and cut the shape of a tree out of my board, which of course, projected a white silhouette instead of a black one. All cookies should have generous opaque borders to prevent light spill. Note the thick border around the bare tree in Figure 3a. If you're working in stiffer plywood, you could make an open-sided cookie, as in Figure 3b, for extra versatility.

If you think you'll use a cookie repeatedly, you may want to make it out of 3/16 plywood instead of foamcore. (Quarter-inch ply is stiffer but heavier -- take your choice.) A power scroll saw works well enough, but I prefer the high-performance rotary tool that uses a drill-type saw and operates like a router (such as a Dremel tool, or a Black and Decker RTX, for example), for close control over the finer details.

Cookie Setup

To deploy a cookie effectively, you'll need a century stand or similar stand-and-clamp to hold the sheet in position, plus a spotlight to shine through it. The light source should be a spot, because it produces a hard-edged beam that creates good shadows. (I like a unit with a lens, for even better control.) Four-way barn doors are a must, to keep the light from spilling around the edges of the cookie and ruining the effect.

Now you see why the cookie has to be at least two feet square. To get a well-defined shadow, you need to place it well out in front of the light source. Move it in and out to create just the edges you want; then barn door the spot to keep the light within the cookie area. If necessary, widen the light masking by adding free-standing flags.

To adjust the overall intensity of your silhouette, move lamp and cookie nearer to the background or farther away. (It's difficult to dim a halogen spotlight without warming up its color temperature.)

Now about that rake on the Venetian blind cookie. If you try to create this effect with a square-cut outline, you have to turn the cookie at an angle. This makes it much harder to keep light from spilling around it, and the near end of the shadow will be softer than the far end because it's closer to the light source. By building the diagonals into the cutout, you can place the cookie at right angles to the light.

Special Cookies

If you think the bare tree cookie (Figures 3 and 3b) is tricky to cut and handle, you're right. Instead, I get the same effect by carrying a fan of dead branches from an actual shrub and clamping them up in front of the spotlight with a C-stand. It works great and I can simulate a windy day by moving it slightly during the shots.

Branches complete with leaves work even better. Just clamp 'em up, aim a fan at them, and check that realistic rustle on the background. BTW, I think this effect works better when the leaves are close to the light and their edges are very soft.

Perhaps the ultimate moving cookie is the fire hula skirt: a curtain of skinny strips hung in front of an orange-gelled light and moved slowly by a crew member to create a flickering effect. In the past, we've suggested thumb-tacking newspaper strips to a stick, but I find that thin but opaque cloth can be rolled up and reused when needed (

Figure 4). Finally, don't forget that cookies don't have to be realistic. In studio situations, you may want a frankly stylized look to project on a background--for example, try a vaguely urban roof line silhouette (Figure 5). Placed above and in front of a gray curtain, this cookie can work very well. However, if you're going to do this often in your studio, consider investing in one of the ellipsoidal spots-with-gobo described in the accompanying sidebar.

Good lighting!

What's in a Word?

"Cookie" is short for "cucalorus," a word so obscure that Google turns up only the information that its origin is not, in fact, Greek, and that it may or may not be named for a character in a fairy tale (um, okay). Cookies are sometimes classed as a subset of "gobo," a theatrical term for silhouettes used to throw shadows and/or color patterns.

Widely employed at plays, rock concerts, and clubs, true gobos are usually placed inside lights of a type rarely used in movies (ellipsoidal spotlights, a.k.a "lekos"). Freestanding cookie-type gobos are also used sometimes in stage applications.

Some claim that the word gobo derives from "go-between;" but there's no evidence for this, and anyway, if that were the case, why wouldn't the short form be "gobi?"

Contributing Editor Jim Stinson is the author of the book Video Communication and Production.

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