fotometrisissa

Fotometristisesti or fotometrisissa is a Finnish term form used to describe things related to photometry, the branch of science that measures visible light as perceived by the human eye. The word is derived from fotometria (photometry) and fotometrinen (photometric). In practice, fotometrisissa is used to indicate measurements, instruments, or methods that operate within photometric principles, often appearing in phrases like fotometrisissa mittauksissa or fotometrisissa järjestelmissä.

Photometry focuses on the human visual response to light, weighting spectral power distributions by the photopic luminosity function. This yields quantities such as luminous flux (lumen), illuminance (lux), and luminance (candela per square meter), which reflect perceived brightness rather than raw radiant power. The photometric approach is distinguished from radiometry, which measures radiant energy without regard to human vision.

In Finnish technical and scientific literature, fotometrisissa contexts are common in lighting design, display engineering, photography, and astronomy. Photometric principles underpin standards and specifications used to evaluate light sources and scenes so that measurements correspond to how people perceive brightness. Typical uses include describing measurement methods, calibrating instruments, and reporting results in a way that emphasizes perceived illumination rather than physical energy alone.