When enabled, Document Grouping on ImageSilo includes a maximum of 100 search results per document.  By default, the Search Results page displays a maximum of 100 documents (including grouped documents).  This means if you have 275 identically indexed documents and document grouping is enabled, a total of 3 search results pages will be displayed.  2 pages will display 100 grouped documents per page, and 1 page with 75 grouped documents.