Consider two outdoors photos taken with different cameras and different cities. You want to include both in the same photo series and therefore need to re-touch them with identical color profiles and effects as much as possible.
With photo #1 and photo #2 open in your software editor, how can you colorize (Hue/Saturation, etc) the lake in the first so that it has the same color as the sea in the second?
Obviously neither the lake and sea have only one color throughout, but encompass a tightly-defined range of blue or teal. Rather than winging it by eye, which can turn out very wrong, is there some sort of color-dropper tool procedure to match and verify that both are being re-colored to the identical color range while colorizing when adjusting the hue, saturation, etc in tandem?