[measuring land area on maps]

this is great, thanks very much for your help Rick!

Related to the same project:

Another map I have has very unclear color patterns, so I would like to recolor it. The attachment shows in the legend which parts of the map are important. The yellow part can be selected fairly easily with the magic wand, but especially the grayish/purple area is much more difficult. I have tried to work with the histogram and adjustment functions, but have not been successful.

Can you provide some tips as to

a. how to most precisely select the gray area?

a. how to recolor the gray area to a solid color?

[measuring land area on maps]

I am curious to know if there is a way to measure land area of a map.

(see attachment for example, in which I would like to know the land areas of the yellow part of the map...)

There must be a faster way than counting pixels!