Coronado Sol Ranger solar viewfinder. Effortlessly line up the sun in your main scope in seconds. Fastens securely to the top of the telescope mounting ring and projects a small image of the solar disk onto the rear of the viewfinder where it is visible to the telescope user. Center the image in the viewfinder and the scope is aligned with the Sun. It's that easy and fast. The SOL Ranger is a sun finder only and will not work for night time astronomy.