Telescope

Beschreibung

Using the telescope.scad file, the maker can print the parts for a telescope, order the lenses from Edmund Optics, and then assemble it to obtain a working telescope. The maker edits the telescope.scad file to enter the characteristics of the optics such as objective (front) lens diameter, focal length, and thickness and the eyepiece lens diameter focal length and thickness. The OpenSCAD program can then be used to generate the stl files for the telescope using those dimensions.To make sure that all parts are consistent, the same program is used to generate the stl files for all of the parts. The maker sets the printphase to each of its values in turn, renders the model and then exports each part to a separate stl file.The parts are then printed and with the purchased optics can be assembled into a working telescope.I used a 33x223 PCX (plano convex) lens for the objective and a 17x-50 DCV (double concave) lens for the eyepiece. The lenses are specified by their diameter in millimeters then an "x" and their focal length in millimeters. For a Galilean telescope the eyepiece lens has a negative focal length. The magnification can be calculated from the focal length of the objective divided by the focal length of the eyepiece lens (ignoring the sign). So the above lenses would yield a magnification of about 4x.From the current Edmund Optics website, the following lenses are a good choice, the 42x290 PCX lens for the objective (catalog number 20-565) and the 12.5x-50 DCV lens…