Educational series: Fog and haze basics

One topic we’ve found that surprises many people who are interested in using laser is the necessity of fog or haze for aerial laser shows. Read on to see why you need fog or haze to get the most out of your laser setup!

The way that light works, lasers included, is that for a beam to be visible in the air, the light needs some sort of atmospheric material to pass through so the photons of light can refract off the material and become visible. Here’s a comparison of a setup of two laser setups with different amounts of fog/haze:

1) An example of a setup with minimal atmospheric material for laser beams to hit and become vivid and visible. This venue had strict rules that required fast-dissipating, water-based fog fluid, and for that reason, the fog did not hang in the air long enough to keep the beams bright.

2) Here is an example of a laser setup with plenty of atmospheric material. We could keep our haze machine running throughout this show, which kept the beams bright and bold.

As the photos show, the presence of atmospheric material for an aerial laser show makes a world of difference. The more fog or haze is in the air, and the more even its distribution, the better the aerial effect will look. The darker the venue environment is, the brighter the laser effects will look as well. Ideally, a laser setup will have an amount of fog or haze that is thick enough to make the laser show vivid, but not too much to make the audience distracted by the amount of fog or haze in terms of its scent or its “feel” in the air. Having plenty of fog or haze in the air also makes it easier to produce an audience-safe show, because you can more easily see where beams go when they are nice and bright thanks to fog or haze, so you can set safe projection zones more easily. Getting the perfect amount and distribution of fog or haze in a venue takes practice, and a good knowledge of the machine that outputs the material into the air, so you can control the timing and quantity of output to match your space.

For lasers, we have found that various types of fog and haze work well for making laser effects visible in the air. There are several types and brands of machines to choose from to output fog and haze into the air, and we have had good results using machines made by brands like hazebase, American DJ and Antari for various setups. What type of fog or haze machine you need will depend on what kind of atmospheric effect you want or need to create, based on the venue and any rules regarding fog and haze that the venue may have. For example, some venues only allow water-based fluids, and some venues require quick-dissipating fluids. Brands like Froggy’s Fog and Antari each offer several varieties of fog and haze fluids to suit your needs.

As you can see, there’s a huge amount of options when it comes to choosing what kind of atmosphere to use and which machine will be best for the task. Here are some basic notes to help guide you:

• Fog fluid
  • Generally dissipates (goes away) quicker than haze
  • Generally water-based
  • Generally has a whiter appearance while dispersing through the air
  • Generally rises faster than haze
  • Generally leaves no residue or scent (scented fog is available)
• Haze fluid
  • Generally hangs in the air much longer than fog
  • Both oil-based and water-based versions are common
  • Generally less obvious in appearance while dispersing
  • Generally stays lower to the ground than fog, as its particles are typically a bit “heavier”
  • Can leave residue or a scent, depending on if oil or water based

Manufacturers today also have a huge range of machines to output fog and haze, in various sizes and for all budgets. Obviously, huge stadium shows and huge nightclubs use several machines at a time for hours on end, but a small venue or concert can most likely get by with one or two machines. Fog machines are generally less expensive than haze machines. Some machines are “hybrids” that produce an effect in between fog and haze, and some machines have more control over output than others.

A quick note about using lasers to do graphics projections is that you do not need fog or haze to make a projection visible on a projection surface like a wall. This is because the projected image only needs to be visible on the projection surface, and having fog or haze in the air where it picks up the projected beams might make the overall display look messy. This may be obvious, but we felt that this is the best place to confirm it.

You’ll have to take into consideration which type of machine is best for the venue(s) your lighting rig is used in, and which kind of fluid will be best for the environment. Overall though, remember that in all environments, laser light needs some sort of airborne material to pass through to make laser effects bright and visible.

Thanks for reading, and if you have any questions about this or any other parts in our educational series, go ahead and contact us!