Volumetric Lighting – Part 2: Atmospheric Effects

We covered the basic of Volumetric Lighting, light sources, and shaping light in part 1. If you haven’t read that yet check it out here. In Part 2, we’ll be covering the three main atmospheric effects used in Volumetric Lighting: haze, fog, and smoke. As a quick reminder, Volumetric Lighting is controllable “rays of light” that you can see. Light is passed through a three-dimensional medium (the effects), just like in the real world. OK, so let’s talk about the atmospheric effects most commonly used by filmmakers…

Haze

The practice of “hazing” is very common in video production and is used in a large majority of commercials, TV and films. “Hazing” simply means you are putting a very thin haze in the air that will allow the light to be more visible. This adds depth and gives your scene a dramatic look. The most common way to achieve this look is with a haze or Hazer machine. Similar to a fog machine, it uses an oil based liquid (for a thicker, longer lasting haze effect) or a water based solution (for a thinner and faster dispersing haze effect). Alternate methods of generating haze include aerosol based haze you can purchase in a can and even burning incense if you’re working in a small enough room. Purchase or rental of an actual haze machine is always preferable to DIY solutions overall. Please note that anytime you use an open flame or hot materials on set you need to have clearance and a safety crew and plan. It must be maintained and observed at all times, no matter how small the source.

Fog

Fog is drastically different than haze in that fog will obscure your shot. Where haze will make the light visible, fog will often decrease it substantially. Fog is great for creating silhouettes and dramatic cinematic effects. Often used in battle scenes, horror movies, and to simulate destruction, fog can be a great tool to increase your production value on a budget. Fog can be used in both foreground and background to add depth or effect. Looking to recreate that creeping fog on the ground effect you see in science fiction and horror movies? A ground fog setup of a fog machine passed through a cooled/ice container will get you the look you want. Fog machines can be purchased many different places, but the cheaper you go, the higher the chance it will not work on set. Many independent filmmakers purchase fog machines from party supply stores or big box Halloween stores only to find they stop working after several uses. There are fog machines specifically designed for extended use (films, night clubs, attractions, theatrical etc) but you will need to invest a little more of your budget for a good one.

Smoke

Many consider smoke and fog one and the same, but I separate smoke here because of the burning process it takes to create it and for its different results and on-set safety requirements. Many filmmakers utilize insect foggers (made for spraying insect repellent and pesticides) filled with mineral oil or oil based fogger solution to create a very thick, smoke-like effect. This method creates a cloud of dense, dark smoke very quickly. It’s a great effect for creating some quick volumetric lighting or simulating smoke from a fire. These “fog guns” run off propane and have an open flame so it is extremely important that you have clearance, permits and a trained operator. As with many areas of filmmaking, Volumetric Lighting is a technique best learned through trial and error. Every tweak of a light and extra pump of a fog machine will have a different effect. Luckily for us, it can be pretty fun! I hope the information in these two articles has helped you to better understand the basics of Volumetric Lighting, and inspired you to use it to create some amazing projects in the near future! Read Part 1 here.