It allows the camera to be properly set and exposed when attached to a waveform monitor. It is especially useful when setting up two or more cameras and getting them to have the same look. Without a waveform/monitor on the set, you probably won't get much use out of them. A good gray card or Macbeth will benefit you in post just as easily.
Ok, if you havent' guessed already I am new to all of this. just to be sure I guess during editing I would compare the Macbeth chart to the computer or TV monitor that I am usiing to display the video while editing. Do I then tweek the colors in the video ( I use Vegas) to match the Macbeth chart? Wouldnt' I use the chart in the field to ensure that my camera color matches the Macbeth chart? This would be for correct field exposure
Thanks for the time and patience. This whole site is great!!!!
You would need a waveform monitor to really adjust the camera for exposure etc. if you were tying to callibrate cameras on set when shooting a MacBeth chart or any other type of chart. But having the chart will allow you to use the settings on post to bring both cameras within the same range by using the color correction tool. The colored squares are for secondary color correction and used mostly by eye, but the white, black, and gray scale can be used quute effectively in post with color correction.