One important research value in Photo grammar is accessibility.
Accessibility means making information available and understandable for a wide audience. Instead of keeping historical archives limited to researchers or institutions, Photogrammar provides open online access to thousands of photographs.
Because the site is publicly available, students, teachers, and researchers can all explore the collection. This reflects a key goal of Digital Humanities, which is to make humanities research more open and accessible.
This meets best practices because it supports accessibility by making historical data available to a wide audience.