this is the biggest issue. Glass transfers heat to the paper and you lose moisture thereby turning the poster into a brittle mess. My 1952R Kong 1sh was framed under glass for 25 years. when I removed it it was brittle and had to be linenbacked.
use plexi
Rich, thank you for sharing this. My understanding is that both glass and plexi have come a long way in the last 10 years. No idea how yours was framed. I assume it was using the best framing techniques available 25 years ago. Heat & humidity are issues that should be addressed by the framer, using sealing techniques to help isolate conditions within the frame from those outside, whatever those might be. As you know that's what you get with conservation frame these days, using all sort of new advanced products.
But ultimately to me it all is about a personal choice, as much as it is about the quality of the materials and frame (and costs). Each of mine have been framed differently. I only go museum glass by a qualifed conservation framer with my most beloved posters. Others, larger posters went acrylic. So I guess I have the best of both worlds
