The ProjectorCentral Forums is a great place to chat with other projector enthusiasts about all things projectors. So, if a white wall is lit with light in the room, then that will be 'black', and the projector needs to get much brighter than that wall to make it appear as black. This is the most important thing to understand. The problem is, that once you start adding light to the room, things change dramatically. So, you can see, that even fairly dim projectors can deliver a 100-inch diagonal image that will be punchy and bright enough in a dark room. Looking at some common screen sizes, the square footage, and actual brightness needed for 18 lumens per square foot is as follows. Some people like a bit more punch, and 20-25 lumens is more than enough to deliver that. The calculation for determining necessary lumens in a dark room actually isn't very complicated.įor home theater use in a dark room, 13-18 lumens per square foot is the recommendation.
But, what does the resulting 1,500 or so lumens of that 3,000 rated-lumens projector actually provide to you in terms of screen size? Well, it all comes down to math.
