polttovälinsä

Polttovälinsä is a Finnish term that translates to "focal length" in English, specifically referring to the focal length of a lens. In optics and photography, focal length is a fundamental property of a lens that determines its angle of view and magnification. It is typically measured in millimeters (mm).

A shorter focal length, such as 20mm or 35mm, results in a wider angle of view, meaning more of the scene is captured in the photograph. These are often referred to as wide-angle lenses. Conversely, a longer focal length, like 85mm or 200mm, produces a narrower angle of view and magnifies the subject, making it appear closer. These are known as telephoto lenses. Lenses with focal lengths close to that of the human eye (around 50mm on a full-frame camera) are considered standard lenses.

The focal length is crucial for photographers as it directly influences the perspective and composition of an image. It also affects depth of field, though this is also dependent on aperture and distance to the subject. Understanding polttovälinsä is essential for making informed decisions when choosing lenses for specific photographic applications, whether it's landscape photography, portraiture, or capturing distant subjects.