I have a presentation in 4:3, but would like to include a single slide from a 16:9 presentation made in beamer. These are complex slides, with subtle layout and animation, so I would prefer not to adapt the slide to 4:3. It is easier for me to admit that one slide will have a different aspect ratio. I was however not able to find any suggestions online, how to change aspectratio for a single frame.
This is one of the things I would like to understand in beamer, to increase my quest in making my beamer presentations more reusable. In Power Point it is relatively easy to glue presentations from existing fragments of other ones.