How to do safe audience scanning
If you are doing audience scanning, it is vital to know how much light you are putting into the audience. The information below discusses how to do these measurements, and what the light levels should be.
The technique described on this page was developed by Greg Makhov of LSDI. It greatly simplifies making safety measurements. Instead of having to measure different parts of a show at different locations in the audience, all that is necessary is to measure a static (non-moving) beam. Then, based on the type of show - static, scanned or “10x” — the laser power is set to a known, safe level.
The audience beams usually have less power as well. This is not a disadvantage. As beams come closer to the audience, they appear brighter. So a lower-power beam aimed towards an audience can appear just as bright as a more powerful beam aimed above the audience.