Fixed projector screen on tv mount (1 Viewer)

[Trivium91]

Hey guys, i have a large basement window that is preventing me from mounting a fixed screen. I can get a tv mount that slides up and down, use a sheet of 1/4" plywood behind the projector screen and attach it to this. This way when im going to watch the projector i can simply slide the screen up which will cover 1/3 of the window. Does this seem like a decent idea? The alternative of course is an electric drop down screen but im afraid of waves and tab tensioned is just far too expensive. Also i think this install will look better.