When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Radiometry - Wikipedia

    en.wikipedia.org/wiki/Radiometry

    Comparison of photometric and radiometric quantities. Radiometry is a set of techniques for measuring electromagnetic radiation, including visible light.Radiometric techniques in optics characterize the distribution of the radiation's power in space, as opposed to photometric techniques, which characterize the light's interaction with the human eye.

  3. Photometry (optics) - Wikipedia

    en.wikipedia.org/wiki/Photometry_(optics)

    In photometric quantities every wavelength is weighted according to how sensitive the human eye is to it, while radiometric quantities use unweighted absolute power. For example, the eye responds much more strongly to green light than to red, so a green source will have greater luminous flux than a red source with the same radiant flux would.

  4. Category:Units of photometry - Wikipedia

    en.wikipedia.org/wiki/Category:Units_of_photometry

    cd/m 2 (= lm/(sr⋅m 2)) L −2 ⋅J: Luminous flux per unit solid angle per unit projected source area. The candela per square metre is sometimes called the nit. Illuminance: E v: lux (= lumen per square metre) lx (= lm/m 2) L −2 ⋅J: Luminous flux incident on a surface Luminous exitance, luminous emittance M v: lumen per square metre lm/m ...

  5. Light intensity - Wikipedia

    en.wikipedia.org/wiki/Light_intensity

    Luminous intensity, a photometric quantity measured in lumens per steradian (lm/sr), or candela (cd) Irradiance, a radiometric quantity, measured in watts per square meter (W/m 2) Intensity (physics), the name for irradiance used in other branches of physics (W/m 2) Radiance, commonly called "intensity" in astronomy and astrophysics (W·sr −1 ...

  6. Exposure (photography) - Wikipedia

    en.wikipedia.org/wiki/Exposure_(photography)

    The use of radiometric units is appropriate to characterize such sensitivity to invisible light. In sensitometric data, such as characteristic curves, the log exposure [4] is conventionally expressed as log 10 (H). Photographers more familiar with base-2 logarithmic scales (such as exposure values) can convert using log 2 (H) ≈ 3.32 log 10 (H).

  7. Photometric system - Wikipedia

    en.wikipedia.org/wiki/Photometric_system

    For each photometric system a set of primary standard stars is provided. A commonly adopted standardized photometric system is the Johnson-Morgan or UBV photometric system (1953). At present, there are more than 200 photometric systems. [citation needed] Photometric systems are usually characterized according to the widths of their passbands:

  8. Photometria - Wikipedia

    en.wikipedia.org/wiki/Photometria

    Photometria was the first work to accurately identify most fundamental photometric concepts, assemble them into a coherent system of photometric quantities, define these quantities with a precision sufficient for mathematical statements, and build from them a system of photometric principles. These concepts, quantities, and principles are still ...

  9. Radiosity (radiometry) - Wikipedia

    en.wikipedia.org/wiki/Radiosity_(radiometry)

    Radiosity of a surface, denoted J e ("e" for "energetic", to avoid confusion with photometric quantities), is defined as [3] = =, +, +,, where ∂ is the partial derivative symbol; is the radiant flux leaving (emitted, reflected and transmitted)