(in visual photometry)
121List of optical topics — Probably some Wikipedia articles on topics in optics are not yet listed on this page. If you cannot find the topic you are interested in on this page, the article may nonetheless exist; you can try to find it using the Search box, or look in and… …
12240 Eridani — Observation data Epoch J2000.0      Equinox J2000.0 Constellation Eridanus 40 Eridani A Right ascension 04h 15m 16.320s[ …
123Radiant energy — Visible light (a form of radiant energy) scattered by fog in a forest. Radiant energy is the energy of electromagnetic waves.[1] The quantity of radiant energy may be calculated by integrating radiant flux (or power) with respect to time and …
124Foot-candle — A foot candle (sometimes foot candle; abbreviated fc, lm/ft², or sometimes ft c) is a non SI unit of illuminance or light intensity widely used in photography, film, television, and the lighting industry. The unit is defined as the amount of… …
125Radiance — For other uses, see Radiance (disambiguation). Radiance and spectral radiance are radiometric measures that describe the amount of radiation such as light or radiant heat that passes through or is emitted from a particular area, and falls within… …
126Airmass — For air mass in meteorology, see air mass .In astronomy, airmass is the optical path length through Earth s atmosphere for light from a celestial source.As it passes through the atmosphere, light isattenuated by scattering and absorption; the… …
12744 Nysa — Discovery Discovered by H. Goldschmidt Discovery date May 27, 1857 Designations Alternate name(s) 1977 CE …
128Maia (star) — For other uses, see Maia (disambiguation). Maia, 20 Tauri Maia is located in the upper right section of the map. Observation data Epoch J2000      Equinox J2000 …
