Thank you, Niranjan. Can you please take a minute or two to describe how you made the measurement?
I can make some sense of your numbers by observing that 82-3=79=243-164, so if you take e.g. 50% of 79 (=39/40 if only integral values are used) and subtract that from 82, you get 43/42, which is close to your measured 44, and 164 plus 39/40 is 203/204, which is close to your measured 202. I gather that in your 50% example, 43 and 203 are the first tones in the mask that would be fully black. For the other fuzziness percentages the arithmetic would be the same.
So the fuzziness setting seems to measuring the fraction of the distance (measured in tone steps) between a bit lighter than 0 and the low point of the range which, in the special nearly-symmetric case I used, is the same as the distance between the range’s high point and a bit darker than 255.
By the way, when I tried doing color range midtones 120-136 with fuzziness 100% on a black-to-white gradient, the transition in the mask from white to black (just viewed on the screen, not measured in any way) was a long gradual gradient, which points to the implicit assumption in the preceding paragraph that it’s not the width of selected range that determines what the fuzziness percentage represents but rather the distance of the low and high points to black and white, respectively.
This is a useful result for me. I feel an emerging curiosity about what happens with asymmetric ranges, which maybe I can look into more carefully before too long
Thanks.
Jeffrey