A simplified method of making the so-called blue slide (Diazochrome slide) is described. Our method consists of five steps: (1) copying the original material with Kodalith film, (2) developing the Kodalith film, (3) exposing the Diazochrome film, in contact, emulsion to emulsion, with the Kodalith negative on the regular chest roentgen ray view box, (4) developing the Diazochrome film in the ammonia jar, and (5) mounting the finished film. A suggested exposure time for the Kodalith negative is one second at f/8 to f/11. A suggested exposure time for Diazochrome film is one hour, and development time for Diazochrome film is five minutes. One should, however, establish his own best exposure time of these films for his own setup. Our method is relatively simple, fast, economical, and convenient.