Protecting B&W mounted prints from the sun

Not even sure where to put this question, so here it is. I'm fortunate to be friends with a couple who has accumulated a very impressive collection of photographs, and likes to display them on the walls in their home. Many of the images are from the 40's and 50's by very well known photographers like Yousuf Karsh. All of the photos are black and white and have glass covering them. Their dilemma is that they want to display their photographs in a room with large glass walls/doors that face to the east. Keeping their blinds open to get natural light into the house also exposes the photographs to sunlight for most of the day.

Because most of their photographs are pretty valuable and difficult to replace, they are concerned about what long term affect/damage the sunlight coming into direct contact with the photographs may have on the photos.

Do any of you have any good advice for them (other than keep the blinds closed)?

You's want museum quality glass that will block UV. Scroll down a bit and you'll see it here. It won't be cheap, and its heavy glass. Still, no painting/print/photo should be exposed to direct sun light. That's just asking for trouble. So hopefully the glass you describe in the home is UV resistant as well.

http://www.frameusa.com/blog/what-are-the-different-types-of-picture-framing-glass/

Schott Mirogard glass is the answer, but no longer than a few weeks max 3 Months. If you friends have several photographs they should change them every few weeks. The Problem with direct sunlight is not only UV light but also heat, that attacks the Emulsion and also causes gassing out. The Frames if not made from the best most archival materials will react to the heat and UV light and will gas out and attack the photography (Wood, plastic, some lacquers), if even a Minute amount of photochemistry still remains in the print it will gas as well and attack the print.

Schott Mirogard plus archival Frames plus archival backing (the biggest culprit) and regularely replacing the photographs on the wall with another one is the best solution.

All visible light and UV and infrared cause degradation to art. Intensity of the light is just as important if not more important than the type of light. You can have an image behind 99% percent UV glazing fade worse than an image with no UV glazing in the same room, but just a different wall because intensity can vary so much. Direct sunlight can cause a 10X increase of the overall intensity of energy the image is being exposed to. Direct sunlight will also cause drastic temperature changes which is also harmful.

If they really care about the images they will scan the images and frame prints of the scans and keep the original images in the dark in a temperature and humidity controlled room.

An easy solution (we have expansive glass facing West) is to have an appropriate film placed on the windows. We have had that for 39 years opposite a gallery wall in our house with no indication of fading.

http://www.jeffreyglasser.com/