Lyric Contrast Mask
The Lyric Contrast Mask filter is a color-correction effect that simulates the classic dark-room contrast-mask procedure. It's prime effect is to reduce the dynamic range of the video, both smoothing the tonal range and pulling detail out of the highs and lows. It is most commonly used to restore detail to high-contrast material. It can also be used to reproduce the 50's style color postcard look, flat with slightly-over-saturated colors, as in the example on the left above.
The effect is produced by overlaying the video image with a mask made from a desaturated, inverted and blurred version of itself. This has the effect of overlaying a softened light on the shadows and a softened darkness on the highlights, hence flattening the overall tone. The main controls in the filter control the overlay mask blur and the blending level of the overlay. There are also standard levels and saturation controls - it is common to get a saturation boost which you'll want to tone down and the natural tone narrowing can be opened up as needed with the level & gamma sliders.
The Lyric Contrast Mask filter includes a set of effect controls that are common across all Lyric effect filters. For a detailed description of these controls, please see the Common Effect Controls documentation.
Additionally, all Lyric Effect filters can be applied through mattes or masks to constrain the filter effect to particular areas of the image. For background information on mattes and masks, please refer to the Lyric Matte Primer.
The Mask Blur slider determines the overlay mask blur amount. It's default value is generally satisfactory, but you can sometimes get light halos around object edges and this can be reduced by adjusting the blur radius.
The Mask Blend slider sets the blend level for the mask, higher values yield heavier tonal correction.
The Level Adjust section contains standard tone level and saturation controls. The White Level sets brightness level in the source image that is scaled up to full-white, so moving it to the left increases overall brightness of the image. The Black Level sets the brightness level in the source image that is scaled down to full-black; moving it to the right decreases overall brightness. Moving the Gamma to the right pulls the midtones towards white, lightening the scene without lifting the blacks or blowing out the highlights; moving it to the left pulls them towards black, again without overly darkening the highlights or dropping the shadows.
As mentioned above, initial application of the filter can result in boosted saturation and a narrowed tone spread that can be further corrected with the level controls. It may be useful to view the clip on the Video Scopes while dropping the White Level slider to bring up the whites and bringing up the Black Level slider to drop the blacks.
The Effect Controls section is a set of common controls that are documented on the Common Effect Controls page. They can be used to achieve masked and other specialized filter effects.