I have a keyword of "Wheeling" (named for the city in West Virginia, not any other Wheeling's that might exist); and another keyword for a nearby location which is "North Wheeling Historic District".
I want a smart collection/smart publish collection that finds all photos with the keyword "Wheeling" and the state of West Virginia, but said collection should not contain any photos with keyword "North Wheeling Historic District".
This obviously won't work, the resulting smart collection contains all photos with keyword "Wheeling" and keyword "North Wheeling West Virigina".
Also, this won't work because it will wind up excluding all photos with keyword Wheeling (which isn't what I want)
After a lot of trial and error, I came across a solution, using Boolean logic and a little known feature of the smart collection/smart publish collection dialog box
To create this "None of the following are true", you hold down the Alt key (that's Windows, I'm not sure what the Mac equivalent is, although I am sure there is indeed a way to do this on a Mac) and then click where the + sign is (actually the Alt key changes the + to a #) on the line that says "State/Province is West Virginia" to bring up this additional dropdown menu in red, select "None of the following are true".
So, I have now defined a smart collection/smart publish collection that finds any photo with keyword Wheeling in state of West Virginia, but if the photo contains keyword North Wheeling Historic District, it is not included in the smart collection/smart publish collection.
Good tip. (Hiding the option to add nested criteria is pretty bad UI design.)
The Mac equivalent of Alt is Option (Opt).