Fixed-focal-length standard lenses have minimal optical aberrations and produce higher image quality compared to most lenses of the same class. They also typically feature a larger maximum relative aperture—some 135-format standard lenses offer maximum apertures as high as f/0.9, f/1, or f/1.2—ensuring sufficient light intake even under low-light conditions. Additionally, standard lenses are compact and highly portable.
The focal length of a standard lens varies depending on the film or sensor size of the camera, but it generally aligns with the diagonal length of the image frame, resulting in an angle of view of approximately 40–53 degrees. The images captured with a standard lens closely resemble the normal field of view of the human eye, and their perspective is similar to what we perceive naturally, allowing for a lifelike reproduction of the subject. In photographic creation, by employing different techniques and approaches, photographers can use standard lenses to achieve effects similar to those of wide-angle or medium telephoto lenses. For instance, when focusing on a very close subject and using a large aperture to shoot a close-up or short-range scene, the background can be blurred to mimic the effect of a medium telephoto lens. Conversely, when focusing on a mid-range or full-scene subject with a small aperture, both foreground and background can remain sharp, producing an effect akin to that of a wide-angle lens. The standard lens holds an underestimated and significant role in creative photography.