Known for their high build quality and precision optics, Panasonic lenses have become the industry standard for professional video applications all over the world. The Panasonic ETELW03 Zoom Lens (0.8.:1) is no exception. It allows you to vary projection distance by adjusting the focal distance, which for this lens is 30mm. It has a standard-throw ratio (0.8:1) that fluctuates depending on the aspect ratio of your projector. Lastly, the ETELW03 zoom lens can compensate for miscalculations during installation.