A standard tool in movie making is a fog machine. Fog adds atmosphere to a shot, reduces contrast, softens the image and can create shafts of light.

Fog machines are great for shooting night exteriors because a few small light units can illuminate a large area when fog is present. The light hits the fog (as in this image with the rocking chair) and that adds an additional lit element to the frame. After all, light needs to hit something for the human eye to see it. Choose a night that isn’t windy as it will sweep your fog away…

For interiors, check that the room you’re shooting in doesn’t have a super-sensitive smoke detector. Use a piece of foam core, grip flag, or some poster board to fan the fog throughout the room for even distribution. Your objective is to build up the level of the fog throughout the room gradually, and let it settle slightly before shooting. It’s often better to have a general haze in the room rather than a lot of smoky swirls. For shafts of light, use a strong, focused light source and aim it downward through the fog. The shot on the right is from Citizen Kane, a movie famous for epic shafts of light like this.

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Illuminated atmosphere, such as fog, becomes a whole separate light source. The trick is deciding how to expose and light the scene. There are lots of different ways to illuminate fog. An unfocused light source, such as an openfaced light, a flood light or other utility light will make the light bounce all over the place. This is a good way to create glow and bring up the overall light levels in the room.

For shafts of light, you need a focused light source, such as spot light, fresnel light (a light with a lens on it which focuses the light into a beam), Xenon light, theater lights, or even halogen lights.

Many people buy fog machines for Halloween parties, and then they go on sale round about November 1st. That’s also a good time to check out eBay for bargains. You’ll also need to buy a bottle or two of “fog juice,” the stuff that makes the fog when pumped into the machine. Fog juice has a very distinctive scent that always makes me think of a zombie movie I worked on once, called the “Bacon Wagon” (no, I’m not kidding). I’m going to keep my eyes peeled for an inexpensive fog machine because I think it can add an extra dimension to my photography.

All of the images I’ve used here are from great films. From top to bottom, these are Road to Perdition, The Village, V for Vendetta, Citizen Kane, Close Encounters of the Third Kind, and Seabiscuit.