Can EasyCatalog search in sub-folders for images?

EasyCatalog will only look in the folder that you have specified in the Field Options for the field. This is mainly for performance reasons, as searching sub-folders each time an image is placed could adversely affect performance. However, if the path to the image can be determined using the content of other fields then custom field functions can be used in the ‘Location’ field.
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In this example, 'FIELDSTR(brand)' will be replaced with the content of the ‘brand’ field to build the path to the image.

Alternatively, a new custom field can be created in the panel that will search a folder structure for a file.  Create a new custom field by following the instructions here.

The ‘FOLDERDEEPSEARCH’ custom field command can be used to search a folder structure: e.g.

FOLDERDEEPSEARCH(‘Macintosh HD:Images’,FIELDSTR(my_image_field))

The first parameter to this function specifies the top level folder to start searching in, the second parameter specifies a regular expression that is used to match against files in the folder.