The Picture Archive Council of America (PACA) has released the "Digital Imaging Standards", Version 2.2 (First presented on 11/15/2003; revised for PDF format on 1/15/2004), written by PACA’s Digital Imaging Standards Committee (DISCo) -- 48 insightful pages:
Immediately, metadata (textual image information) surfaced as the biggest concern. Photoshop’s IPTC structure, developed for newspapers, causes confusion when applied to “stock” images...both rights-managed & royalty-free. It’s poorly utilized & understood by archives & customers alike.
Inconsistent use of metadata undermines the protection & control of image rights. For example, customers might look for image credits in the wrong place, or over-write the creator’s copyright notification.