The baffle calculator need four input parameters. The telescope tube is modelled as a cylinder with a given Inner Diameter and Length, with a cap on each end. Each cap has an opening (or aperture) of a given diameter centered in it. The purpose of the baffles is to keep stray light entering the tube from the first end (entry), scattering off the tube wall, and leaving the tube at the other end (exit). The baffles cannot, however, are not allowed cut through the direct light path from the entry opening to the exit opening, or light used to form the final image may be lost.
After selecting the input values, hitting the Calculate button provides the results. Each baffle is numbered and provided with a position in the tube and the minimum hole diameter. The positions of the baffles start with zero at the entry point of the tube. The maximum reflectance point position is also given. At each end of the tube, the last baffle typically protects more of the tube wall than is remaining.