A film print or digital projection master can be quite different from a television broadcast master. The most common area of this variance is in the black levels. In a darkened theater, thin (grey-looking) black levels on the print or digital projection can yield the impression of rather flat looking imagery. To avoid this effect, a lot of attention needs to be paid to the black areas of the video signal during color timing and shooting. Variations in the black areas of the signal can be accentuated during the transformation from digital to film due to the differences in the gamma responses of these different mediums. As well, many of the common video rules for broadcast black levels don’t necessarily apply to a film output or digital projection. Television broadcast standards (sometimes referred to as broadcast “clamping” or “legalizing”) of black and white levels are not recommended for most film output. Since film negative has a much wider latitude than video it can actually see into areas of black that you are may not be seeing on the monitor, depending on how that reference monitor you are using is set. It is very important to test your black levels by getting Central to output a small section of your color corrected digital images onto film before proceeding with a full color correction of your project. Remember, wave-form monitors are the only real indication of the black and white levels (see "Use of Monitors/Wave Forms"). Just because it looks okay on the monitor doesn't mean your black levels are optimal for film output or digital projection. Monitors do not always show if there are variations in black levels. Always look at the signal information on a properly set up wave-form or vector-scope. If you are not sure about your black level consistency, contact one of our Digital Film Specialists and set up a consultation session between Central and your colorist, or send us an example of your existing color-timed master. |
