Saturation

The Saturation tool allows you to highlight pixels in the live image that are above and/or below a certain grayscale value threshold.  Typically this tool is used to highlight in red all pixels that are saturated -- i.e., at their maximum value.  You can, however, configure the tool to highlight pixels higher and/or lower than any grayscale value you specify, and you can apply the threshold to all three color channels or to any single color channel or a combination of color channels.