Variables need an image to evaluate from, they are not parameters for searching. When you follow the
search examples and do a search like
caption "the lazy dog."
"caption" specifies the name of the field that the search needs to be performed on; if its not one of the fields listed in
searchable fields then it is not a field in your database. You can think of your catalog database like a big spreadsheet. All of the filenames of the images you've added to your catalog are in a column in the spreadsheet called 'filename', so when you do a search for "filename is IMG_1234.JPG", it is looking in the filename column for matches.
I'm thinking of writing the character returned by fbas to an unused metadata field and searching on that but wonder if there is a direct way?
That could work, I suppose, since it sounds like the "bad" images would return a dash and the good ones would return a period and you could then sort them that way. But how many ingests did this occur for? If it wasn't many, wouldn't it be simpler to just go to the folders where the problem happened and use some variation of substring extraction to chop out that piece of the data?