Need more to get this to work.

Feb 12, 2015 at 11:19 PM
Edited Dec 30, 2015 at 12:53 AM
You 're missing one step, where a workflow needs to be created to copy the Document Name to the Title column.
Or javascript feature from spjsblog.com which copies the filename to Title column.

SharePoint is unable to reference the Name column in a calculated column.
The Title Column in the Calculated Column is required to display the PDF on mouse-over.

If you have a look at my Blog here: https://sharepoint2020.wordpress.com/2013/11/04/add-a-pdf-thumbnail-hover-preview-column-to-a-document-library/

This explains how to implement this for SharePoint 2010 which can be adjusted easily for SharePoint 2013.