135 / Full-frame Lenses

35 mm film, full-frame DSLR, full-frame mirrorless, and rangefinder systems | 36 x 24 mm image area with a 43.3 mm diagonal

The 135 still-camera frame became the dominant small-format photographic standard in the twentieth century. Its 36 x 24 mm image area defined familiar focal-length categories: 28 mm wide angle, 50 mm normal, 85 mm portrait, 135 mm telephoto, and many more. Because so much photographic vocabulary grew around this frame, other formats are often described through their full-frame equivalent angle of view.

Full-frame digital cameras inherited that geometry, making 135-format coverage the modern reference for many optical comparisons. The format is large enough to demand careful correction across a broad field, but small enough to support fast primes, compact rangefinder lenses, professional zooms, and highly specialized optics in one ecosystem. A full-frame lens has to serve roughly a 21.6 mm field radius, so astigmatism, coma, distortion, vignetting, and lateral color become visible design pressures toward the corners.

The catalog's 135 entries span rangefinder, SLR, DSLR, and mirrorless systems. That makes the format especially useful for comparing how the same image area behaves under different mount constraints: short-register rangefinder lenses, retrofocus SLR wide angles, long-back-focus telephotos, and modern mirrorless designs with more freedom near the sensor.