In addition to standard keywords, ON1 Photo RAW 2020 also supports the creation and use of hierarchical keywords. This option lets you “nest” keywords within a top-level keyword, which can be helpful to manage and categorize keywords.
For example, you might want to use a master keyword for states that you’ve visited—“California,” “Nevada,” “Oregon,” etc.—and use sub-keywords for places within the state, like “Death Valley,” “Joshua Tree”, “Valley of Fire” and others.
Hierarchical keywords are displayed in the Keyword pane with a small right arrow to the left of the top-level keyword. Clicking on the arrow will display the sub-keywords for that master, with the number of images with that keyword on the right side. As is the case with standard (i.e. non-hierarchical) keywords, you can double-click on any of the nested keywords to show all of the photos in your cataloged folders that use that keyword.
To create a keyword hierarchy, first create your master keyword by clicking on the gear icon at the top
of the Keyword List pane and choosing Add Keyword. Enter the name of the top-level keyword and click Apply. (If you have photos selected, and don’t want to add the new keyword to those images, uncheck the “Add to Selected” box before clicking Apply.)
To create a new nested keyword, right-click on the master keyword and choose Add Keyword from the pop-up. The dialog box should now give you a check box to nest the new keyword inside the top-level keyword, as well as to add the new keyword to any selected photos.
If you wish to create new hierarchies from existing keywords, it is best to first create your master keyword, and then drag any existing keywords onto that master.