I painted a goo screen on the wall after setting the size off a dvd player hooked to the projector via s-video. Now I hooked up a PC to the Projector via the s-video out on the PC and the image is smaller. Projector is native 4:3 and the computer is running a 4:3 resolution. Why is the image size through the projector different? I thought it was the app I was running but even turning the extended desktop white shows the entire screen is not being used. Probably 3"-4" all the way around the screen. Thanks in advance.