600MM FOCAL LENGTH; 50MM 2-ELEMENT ACHROMAT AIR-SPACED OBJECTIVE LENS; FULLY-BAFFLED ALUMINUM TUBE FOR EXCELLENT VISUAL & CCD IMAGING; MULTI-COATED OBJECTIVE WITH RESOLVING POWER OF 2. 28 ARC SEC; DIAGONAL CONSISTS OF 45 SCHMIDT PRISM THAT IS FULLY COATED IN MAGNESIUM FLUORIDE WITH REFRACTIVE INDEX ...