Choosing the correct lens is critical for large venue projection. This guide explains how to calculate projector throw ratio using screen width and lens-to-screen distance, and compares SMX interchangeable lenses for 10,000–25,000 lumen large venue laser projectors. With lens ranges covering approximately 0.53:1 to 7.51:1, system integrators can select short, standard or long throw optics for auditoriums, stages, events, museums, immersive installations and projection mapping projects.