A Clean Plate (shown above) is a clean pass of the backing material without the foreground present. Identical to the Action Plate (shown above), but differs in that foreground elements are not present. In the case above, the Clean Plate and Action Plate are identical except for the actors and their shadows.

PHYX Keyer contains two plugins which require a proper Clean Plate to operate properly: DiffKeyer and ScreenCorrector. Under most conditions, you will apply these plugins to your Action Plate.

DiffKeyer works by comparing the Clean Plate and the Action Plate, (which contains the objects or actors you wish to key) and creates a matte for the foreground objects. We recommend to use stationary backgrounds and to NOT use moving backgrounds (blowing leaves, water, etc.) with DiffKeyer as movement may create undesired differences between the Clean Plate and Action Plate. DiffKeyer does not require a green / blue screen Clean Plate.

ScreenCorrector uses the Clean Plate as a reference to correct defects (uneven lighting and other ‘garbage’) to make the backing color an even green or blue.