Photographic images
We perform evaluation of the permanence of images in accordance with test programs developed together with our customers.
Both conventional photographic material and images produced with e.g. inkjet printers can be evaluated.
Light fastness is evaluated in test programs where the images are subjected to light similar to daylight but with much higher intensity so that the results are obtained in short time. What is often called UV-permanence is tested in this manner. This is a misleading term since the UV-part of indoor light is very small.
The image to the right was illuminated. The colours have changed, especially the yellow colour.
PAT-test
PAT-test (Photographic activity test) is used for evaluation of the influence of the storage materials (folders etc.) on the photographic image. Keeping the storage material in contact with two types of photographic detectors and following the changes in optical density of the detectors performs the test.
Many archives and museums are using this evaluation method before choosing their storage materials. A positive result is interpreted so that the storage material will have no negative effect on the images.
Labels and self-adhesive tape may be tested with this method.