I find that certain projector's show up as way brighter than they actually are in the calculator. The interesting thing is that I can see that the correct brightness is entered into their site, but it winds up being way off. For example, try plugging in the infocus screenplay 4805 and use it with 100" diag screen, (16:9) then take a brighter pj, like the Optoma HD91, use the same settings and screen size and you will get an image that is about 25% dimmer. Why is that? I am using home theater mode on both of them but the Infocus is the one that is showing up as brighter than it really is. I have seen this numerous other times, random projectors showing as about twice as bright as they really are for a given application (I am verifying that they are being used for HT or presentations where appropriate, I know that HT knocks the brightness down to 50%).