FogContrary to popular belief, fog machines are not just helpful tools used to set the mood at awkward middle school dances. In fact, as many of you might know, fog (or haze, but we'll get to that later) is widely used on film sets for a number of reasons, one of which is, yes, to set a specific tone, but it can also be used to pull off many different stylistic, technical, and aesthetic effects. In this helpful video, Film Riot's Ryan Connolly shows us how using fog can help you add depth to your shots, diffuse light, or simply create a creepy atmosphere befitting of a slasher film. Also, learn how to get the most out of your fog machines with a couple of cheap, DIY tricks.

The first time I ever rented a fog machine was for a B-movie style monster movie I was shooting in college. My thought was, of course, "There's a monster on the loose stalking innocent teenagers. Of course there's fog." However, it never occurred to me that using fog could've helped that production, as well as countless others by diffusing light, softening shadows and highlights, and adding depth to my shots.

Again, there are many different ways fog can help create a specific look and set a tone for your film, but it also helps to give your scene, as Connolly says in the video, a "Spielbergian vibe", because it not only diffuses light, but it carries the color of the light throughout the space you're using for your scene.

Here are a few examples of "Spielbergian" fog from, you guessed it, Spielberg movies:

Here in E.T., Spielberg uses fog to not only diffuse the light from the spaceship, but to create a dreamlike mood.

Fog is used to create an abandoned-looking atmosphere, as well as to heighten the mystery and anticipation for what could be lying in wait in this scene from Jurassic Park. (Start at the "back in business" part at 1:58.)

Spielberg's use of fog in this scene from Lincoln is wonderful, because it not only shows how subtle the look can be, but also how effective it is. You can actually see it billowing from the left side of the screen when the camera is on Lincoln, but it's use in the background for the two-shot to create depth as well as solidify the film as a period piece.

I tried to find those iconic flashlight beams from Jurassic Park (I will call them fogsabers), but was unable to come across a scene online, but thankfully Film Riot includes just such a clip in their video. Connolly touches on the many ways fog can help the look of your film, so check it out below.

Now, if you're going for that quintessential zombies-in-a-cemetary fog, here are a few things you should know. First of all, the fog that comes out of a fog machine is probably going to be too thin for that luscious, thick fog you're looking for. The main reason for this is because the machine heats the fog juice to a temperature that thins it out, which will not only allow it to dissipate quicker, requiring you to keep pumping it out, but it won't be heavy enough to withstand even the smallest amount of wind (if you're shooting outside -- in a cemetery).

One solution for this thick, heavy "movie fog" would be to use dry ice, but if that's not your bag, there is an alternative: cool down the fog that comes out of your fog machine. This simple tutorial shows you one cheap, DIY way to pull it off using a PVC pipe, ice, and a cap with holes in it.

Fog machines are usually dirt cheap, ranging anywhere from $30 to $150 or so depending on how big/small it is and where you buy it, and renting is even less expensive. (If you want to go even cheaper, you can make your own fog juice by mixing 1 part food grade glycerine and 3 parts distilled water.) However, it should be noted that fog isn't generally used on big productions, like the Spielberg flicks I mentioned above. These bigger films usually use hazers, which evenly distribute a thinner, sometimes invisible haze. It's used mostly to make light beams appear on-camera and to apply light diffusion, but these machines require a huge investment -- anywhere from $300 to the thousands. Though, I have heard that adding a little bit of water to your fog juice can dilute the solution enough to give you something haze-like.

Fog isn't the only way to pull off light diffusion, depth of field, or even fog effects (you could apply it in post if you really wanted to), and you may not even want the look it produces. (Maybe you're going for the high contrast.) But, hopefully you can go forward with a little more understanding of just how versatile fog actually is, and use it in the future to create some awesome effects!

Share your thoughts on how you implement fog in your projects in the comments below!

[via Film Riot]