Erfle

Erfle refers to a family of wide-angle photographic lenses developed in the 1930s and named after the German optical designer Rudolf Erfle. The design emerged during the early boom of 35mm photography and was produced by several European manufacturers, notably in Germany. Erfle lenses were among the earliest practical wide-angle options for 35mm cameras, offering a broader field of view than standard 50mm lenses while remaining compact enough for everyday use. They were widely used on early rangefinder cameras and later on some early single-lens reflex bodies, and various versions appeared in focal lengths around short to moderate wide-angle lenses.

Optical characteristics commonly associated with the Erfle design include a relatively simple, compact multi-element construction intended to minimize distortion and maintain a practical level of sharpness across the frame. They typically exhibit good color rendition for their era, with some softening at wide apertures and noticeable vignetting or edge softness by modern standards. Coatings and manufacturing tolerances improved over time, reducing flare and image degradation.

While later lens designs supplanted the Erfle in many applications, the design remains notable in the history of photography for shaping the development of practical wide-angle lenses. Today, Erfle lenses are of interest to collectors and enthusiasts for their historical significance and distinctive rendering.