AFTER EFFECTS KEYLIGHT 1.2 WHITE FULL

Ultimatte Green is more pure, with only a quarter the amount of red and no blue whatsoever. Blue isn't pure blue, but double the amount of green, which in turn is double the amount of red. Ultimatte Green screens, meanwhile, are nearly pure green ( see Figure 26).ДЇigure 26 The Rosco colors, left to right: Ultimatte Blue, Ultimatte Green, and Ultimatte Super Blue. In other words, imagine that there are three settings (instead of 100) and try 5%, 50%, and 95%.ДЄ Rosco Ultimatte Blue screen contains quite a bit of green-much more than red, unless someone has lit it incorrectly. The more generalized recommendation from The Foundry, however, is to set it 'near 0, near 100,' and compare the results to the default setting of 50 to evaluate which one works best. In version 1.1v1 of Keylight, that's exactly how the plug-in sets Screen Balance, depending on whether you choose a blue or green Screen Colour setting. On this theory, you would employ a balance of 95% with bluescreens and leave it at 50% for greenscreens. Screen Balance allows you to alert Keylight to this fact. It's even more effective, however, if it knows whether one of the two remaining colors is more prevalent, and, if so, which one. That takes care of saturation, but what about hue (the actual green-ness or blue-ness of the background and foreground), and how pure is it? Keylight is designed to expect one of the three RGB color values to be far more prevalent than the other two in order to do its basic job. This change effectively brings more desaturated background pixels into the keying range if raised or, if lowered, knocks back pixels in the foreground containing the background color. Screen Gain boosts or reduces the saturation of each pixel before comparing it to the screen color. In either case, Screen Gain becomes useful. Similarly, a clear symptom that your foreground is contaminated with reflected color from the background is that it appears semi-opaque. A clear symptom that the background lacks sufficient intensity is that areas of the background have a consistent hue, yet fail to key easily. One major enemy of a successful color key is muddy, desaturated colors in the background. You can adjust them without adding any processing load whatsoever, and they work together to yield the ideal matte the rest of the controls merely correct the result. These top five controls (from Screen Colour to Alpha Bias) differ from those below them in that they work on the color comparison process itself, rather than the resulting matte. The Bias controls color-correct the foreground. Screen Gain emphasizes the saturation of the background pixels, and Screen Balance delineates the background hue from the other primary colors. That's why Keylight adds the Screen Gain, Screen Balance, and Despill and Alpha Bias controls. Those criteria sound vague, not easily met-and it's true, they're somewhat vague, and often not met.

The lesson contained in the table is that a healthy background color has a reasonably high saturation level and a distinct hue. Subtract a mathematically weighted amount of the screen color and make it semitransparent Key out the pixel completely, making it transparent How Keylight Makes Key DecisionsД¬ompared to Screen Color, the Pixel Is.Д¬onsider the pixel to be foreground, making it opaque From that, Keylight makes weighted comparisons between its saturation and hue and that of each pixel, as detailed in the following table. The core of Keylight involves generating the screen matte as mentioned earlier, the most essential step is the choice of screen color. This section offers a glimpse into the inner workings of Keylight, which will greatly aid your intuition when pulling a matte. The Inner Workings of KeylightДЄ few decisions are absolutely essential in Keylight most of the rest compensate for the effectiveness of those few. Before delving into those (in the 'Focusing In' section), let's look at how Keylight actually operates. Keylight anticipates these issues, offering specific tools and techniques to address them.

AFTER EFFECTS KEYLIGHT 1.2 WHITE FULL

Not only that, but the alpha will preview at speed, in full motion. You can switch a RAM Preview to Alpha Channel view by pressing Alt-4 (Mac: Option-4) without losing the cache.

After effects keylight 1.2 white