I received a call last week from a elderly man who had tried to clean an old photograph with some water. Please don't ever do this. He ended up with the "bird blob" right on the face of the photo were the old pigments lifted. Someone gave him my name and against my better judgement, I have done the best that I could. I had to keep a light touch so as not to cause more damage. I will try to make that top lip a little less dark but the paint is being very touchy on this substrate. The other thing I hope to do for him is cut a matt so that the photo is not touching the glass as it was when I received it.
If you have photographs that you value, or think you may ever value NEVER, EVER, EVER place them directly against glass. Over time, a little condensation will creep in and stick the surface of you photo to the glass and then your photo is ruined. USE A MATT! Even a cheap paper matt is better than no matt (although a cheap paper matt will leave a burn edge on your photo over time. If you can, use a
good acid free matt and never hang a photo or print in direct sunlight. Sunlight will fade a photo and will erase colour pigments over time. If you see sun damaged prints...they are nearly all shades of blue, the yellow and reds have been burnt away. With proper matts and framing, photos of this century should last into the next.
There, that is my free advice from years spent picture framing. I hate to think of the number of time people were moved to tears when they came to me with a photo that had sealed to the frame glass, wanting me to fix it and all I had for them was bitter news.