Permanence tests are methods used to determine whether a photographic image will maintain its quality and stability over the long term. These tests assess how well prints, negatives, or digital reproductions resist fading, discoloration, and deterioration under various environmental conditions such as light, humidity, and temperature.
Photographers and conservators use permanence tests to ensure archival quality and longevity of images. By evaluating materials, papers, and inks through controlled testing, permanence tests help identify the most durable photographic processes, guiding choices for printing, storage, and display of both historical and contemporary photographs.