Is there a calculation to test a PDF in a container field to see if the PDF has or does not have a preview? In other words, I have a database with a lot of PDFs imported by Macs and Windows. The Mac ones include the PDF and Windows does not. I would like to be able to test which ones are missing previews so I can run a batch script on a Mac to export and reimport them with the preview. FYI, I'm happy to use a plugin to solve this and have a number of plugins on this server such as BaseElements and MBS. Oh, and while I'm asking, does someone know a plugin that can add a preview to a container field without having to use a Mac to export the field contents and reimport them? Thanks.