For me photography has always been about the light, created, or found and how to control it. With cookies, the possibilities are endless. It can be as simple as a piece of cardboard with shapes cut out of it. I have made them from foam core, large process screens from a copy camera and all types of cardboard. They also can be made from what ever you have on hand. For a large indoor shoot, my cookie was a net that I hung tree branches and leaves from to break up the light. Plastic milk crates are another one of my favorites, but not as portable as flat materials. Glass blocks which are not by definition a cookie, are also great for shaping light. All of these materials can take the otherwise plain background, or subject and give it life. If you want the feel of light coming through window blinds when there is no window, one light and a cookie can do it. All you have to do is think of the effect you want to achieve and make your cookie. Another important tool is a flag, which is nothing more than a black panel used to block light. They are used to remove light from where you don’t want it. They also can be made from black cardboard, or foam core. the larger ones that I use are fabric attached to a frame with both opaque and translucent options. Aside from blocking light from your subject, they can keep light out of your lens to stop flare. This is critical when shooting back lit subjects. Below is an example where I placed a cookie above a model warehouse. I chose to use white foam core so it would also reflect light into the scene. Above the cookie was single light source with a standard reflector. The next image’s background was done with a cookie made from a dark neutral gel cut in a wave like pattern. A blue color correction gel was also added for interest. The light source for the background cookie was shot through a snoot to keep its light off of the subject. To light the subject I used a small soft box and reflectors to fill in shadows.The background behind the copier was made by cutting slits in a piece of black mat board and the light on the copier was also shot through a cookie Both light sources were shot with snoots.