One hundred years ago, a 16-year-old Ludwig J. Bertele began his training as an optical calculator in Munich. The potential of this mathematically inclined young man did not go unnoticed for long: at just over 20 years old, he first captivated the professional world with an innovative optical design that was remarkably powerful for its time. This bright, sharp-focus lens made it possible to photograph indoors without flash and without a tripod for the first time. Subsequently, a camera equipped with this lens became the foundation for the success of numerous prominent photographers. Ludwig J. Bertele's work holds a prominent place in the rapid development of geometric optics and, consequently, photography after World War I. Later, his developments also set standards in aerial photogrammetry and other specialized fields of optics.