From the very beginning, people in the world of stage lighting have been manipulating color to affect the mood of the show.
But what is color?
Color: Noun: The aspect of things that is caused by differing qualities of the light reflected or emitted by them, definable in terms of the observer, or of the lights as:
The appearance of objects or light sources described in terms of the objects hue, brightness, and saturation for the light sources.
The characteristics of light by which the individual is made aware of objects or light sources through receptors of the eye, described in terms of dominant wavelength, luminance, and purity.
This leads us to…
Visible Spectrum: The portion of the electromagnetic spectrum that is visible to the human eye. The spectrum, however, does not contain all the colors that the human eye and brain can distinguish.
Which in turn takes us to…
Unsaturated Colors: Colors made by a mix of multiple wavelengths.
Pure Colors: Colors made up of only one wavelength.
I could keep going on (and on and on), but what does this all really mean to you as an LD?
Actually, everything and nothing.
Just like you don’t need to know exactly how your car works to drive it, you don’t need to know the science behind the visible spectrum to light a show. But, just like knowing your car needs things like gas and oil to run, you should know a few things about color to have a better show.
Color Mixing: There are two types of color mixing: additive and subtractive. Like most things in lighting, it sounds just like what it is.
Color mixing is taking multiple colors and combining them to make one.
Subtractive Color Mixing: This is used with moving lights that have a lamp in them. The lamp creates a “white” light, then you use the color flags (cyan, magenta, and yellow also known as CMY) to manipulate the color. What is actually happening with the color flags is they are filtering the colors out of the “white” light (cyan + magenta = blue, because the magenta is taking the green out of the cyan). All that being said, if you take yellow and cyan you get a green because (as said in the old commercial) “yellow and blue make green.” So while you are adding in yellow and cyan on your fixture, the flags are subtracting the other colors of the spectrum to give you the color green. When you take all your CMY flags to full you get no output because you have filtered out all the visible light.
Additive Color Mixing: This is the new kid on the block. Additive color mixing is used with LED products. Most LED products are red/green/blue (RGB) (NOTE: some also have white and amber). LEDs do not have a “white” lamp in them. You start with zero output then add in the red LED to make red. If you want blue, you turn on the blue LEDs. If you want purple you turn on the red and blue LEDs. To get “white” out of an LED fixture you turn on RGB all at full. Many new led fixtures have a white LED in them because if you take RGB to full, it actually has a lavender-ish tint to it.
Some fixtures do not have color mixing, just a color wheel with about a dozen common colors in it (red, green, blue, yellow, etc.). This is just the same as putting a gel in for a conventional fixture. Just like you can swap gels for conventionals you can swap the color dichroics in moving lights (it just costs a lot more money and time to do it, so think about that before you ask the tour to pay for a slightly different shade of red than what is already in there).
I can feel everyone’s eyes rolling back in the heads already. That’s fine. There is a reason people write entire books on the subject of color. I haven’t even started in with color correction, or how colors react on camera, or for that matter how color can affect your show!
I’m sure you can tell that next week will bring a Part II. And if Part II spirals out of control like Part I maybe there will be a Part III.
Come back next week for Part II where I will talk about Color and Your Show (you know, the kind of stuff I normally do).
Until next time, here’s a fun lighting video from everyone’s favorite scientist.