Navitar's 3.5X fisheye conversion lens is designed to work with lower cost projectors that do not have replaceable lenses. This is an ideal solution for planetariums that want to upgrade their existing systems, but can't afford to buy new projectors or replacement lenses. The new 3.5X Fisheye will also work in many applications where users simply want to project a very wide projector angle onto a curved screen, such as simulation, immersive environments, and amusement parks.