Re: More NG slides, etc

Greg:
The aluminum frames can be removed. The cardboard slide mounts just slide in. This method was used to prevent slides from "poping." A piece of film in a slide mount has a slight bow to it. As the heat from the projector warms up the film, the bow pops out and the slide is no longer in focus. Auto focus projects automatically compsensate for this, but they didn't have auto focus in the days of these projectors. This is the same reason that some mount their slides in glass slide mounts. I think you can gently pull the slides out of those frames. Haven't seen one of those in about 30 years, but I have removed slides from them...just be careful.