Lighting Misconceptions Pt. 2
“Look at how a single candle can both defy and define the darkness.”
― Anne Frank
We use darkness or shadow as a texture with which to define a platform. We do this by employing specific stage lighting. Stage lighting is broken into two main sections: 1)front lighting and 2) effect lighting. In part two of this series we’ll dive into front lighting in greater detail.
It seems that architects, contractors, and a fair share of DIY lighting people understand the need for front lighting but don’t understand the theory behind accomplishing really effective stage lighting. Instead of pointing lights at a stage from the most convenient spot in a room, here is the basic theory to proper front lighting.
Ideal front lighting consists of two separate lights shining across a 45 degree angle toward a specific spot on stage as well as being 45 degrees from both the left and right from that same spot. To gauge this distance a laser measurer is the best tool but some resourcefulness and a standard tape measure can get you pretty darn close. Looking at the triangle above, here are the measurments you’re going to need. Side a is the measurement from the floor to the lighting bar (to be really precise you would measure to the lens of the lighting fixture itself). Side b of the triangle is going to be the measurement from the same spot on the floor from side A to the spot on the stage you are trying to light. Side b should be the same length as side A. this will give you a 45 degree angle at angle B creating your 45 degree beam angle. To measure for your 45 degrees from center take your triangle and lay it on it’s side (side a becoming the line from the center of the room to the spot directly under your lighting bar).
This technique works fine in a square room with a flat-front stage, there is a simple trick that you can use for a rounded stage front or rounded room. Find your distance from the floor to the bottom of the lighting bar. Now cut a length of rope at twice that distance and clearly mark the middle. if you want to be really exact you can tape the rope onto a 90 degree square with the middle point right on the corner. With the rope, measure your distance between the spot on stage and your distance from the middle. then take your horizontal side a and stand it up. The top of the rope is where the lens of your light should end up.
Lighting a face from 2 sides at a 45 degree angle will yield very efficient and effective lighting for general stage lighting as well as video production. In the next part of this series we will discuss the last piece of the lighting triangle, back lighting.