So I will be DMing a new campaign, and we are going to be starting with the module for The Sunless Citadel. I have a very large .jpeg file for all of the dungeon maps, and plan on using my little projector, mounted above the table, to project the map onto the table to use as the battle mat.
Here is the problem, how would I keep from revealing the entire dungeon level to the players all at once, while still being able show the areas they are in/have already been too?
Initially, I was thinking of using a thick card stock (flash cards) and some tape to block portions of the projected image before it got to the table, but that seems like a lot of additional work every time they enter a new room.
Does anyone here have any experience using digital copies of maps and projectors, or even tables with a built-in screen?