ABSTRACT
One of the most Byzantine topics in the digital film domain is the issue of log versus linear film data. It is a difficult subject because it crosses several disciplines, including the human perceptual system, film response curves, and math. Lots of math. A scientifically rigorous explanation of all this would make truly gruesome reading, and I fear most would not bother. Instead, I have taken liberties with precise scientific terms such as “brightness,” simplified the math, tossed out troublesome details, and tried to present an understandable tale that you might actually read, and therefore benefit from. The attempt here is to present the behavior of film and its digital representation as seen from the compositor’s point of view, not the engineer’s. In the end, you will wind up with the same basic understanding of the principles that the scientifically rigorous approach would have given you, but with far less pain. If you want pain, just contact Kodak and request the technical papers on log film digitizing. They will give you all of the pain you want.
