Curves with numerical input

[Aldor]

Sorry, I know, it was raised many times already but it is highly important to add numerical input capabilities to Levels Adjustment!

PS. As a half-useful solution could you please just extend Levels window/dialog with numerical indicators (read-only) of current value of corresponding slider (when slider is changed) and/or values (input/output) of active control point (after click on it or when it is moved/changed).