This effect simply clamps color and alpha values.
Threshold: [ Default 50 ] [ Range 0 - 100 ]
Controls the strength of the threshold.
0 applies a threshold to the darkest values
100 applies a threshold to the brightest values
Soft: [ Default # ] [ Range # - # ]
Controls the hardness/softness of the threshold
Change Color: [ Default ON ] [ Switch ]
Converts the image to grayscale and clamps the luminosity
Change Alpha: [ Default ON ] [ Switch ]
Reads the darkest luminosity values and converts them to alpha
Invert: [ Default OFF ] [ Switch ]
Inverts the operations of Change Color & Change Alpha
Global Opacity: [ Default 100 ] [ 0 - 100 ]
Controls the overall opacity of the effect on the image