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From the Epson 5010 FAQ page.
What image size can be projected?
The projected image size is measured diagonally and can be from 30 to 300 inches (0.76 to 7.62 m). The size of the image is determined by the distance from the projector’s lens to the screen. Depending on your display settings, source signal, and how you use the Zoom ring, the actual size may differ. A utility to help calculate an image size or the projection distance is available from the Drivers & Downloads page for your projector.