Nomad Z
Well-known
The Kindle-style electronic paper seems like a good way to make the mask, and couldn't automatic selection be done using the 6-bit coding that's already on the lenses? For preview, maybe a roller/jog wheel could be used to cycle back and forth amongst a subset of focal lengths that one chooses from the menu (whether presets or custom setups). The idea being that one chooses a subset that matches the lenses one is using.