Explanations RSS

absorption spectrum, chlorophyll a, chlorophyll b, grow light, horticulture, light absorption, PAR, photosynthesis, PPFD, zenith LED grow lights -

  Part 3, PPFD Photosynthetic Photon Flux (PPF) is the total amount of Photosynthetically Active Radiation (PAR) emitted by a light. Measured in micromoles per second (µmol/s), PPF provides a general understanding of a light's full output, but it does not measure the photons that actually reach your specimen. To rationalize the true utility of natural and artificial light, the Horticulture Industry relies on a narrow interpretation of photon delivery by gauging Photosynthetic Photon Flux Density (PPFD). Expressed as micromoles, per square meter, per second (µmol/m2/s), PPFD is an evenly weighted measurement of PAR that falls on a specific spot....

Read more

absorption spectrum, chlorophyll a, chlorophyll b, grow light, horticulture, light absorption, lumens, PAR, photosynthesis, zenith LED grow lights -

  Part 2, Lumens A lumen is a unit of luminous flux that is derived from lux. One lux equals one lumen per square meter. As is detailed by the following LI-COR LI-210R Photometric Sensor, the Lux Response is heavily weighted to measure peak human sensitivity (555nm), because a lux/lumens measurement is specifically designed to assess the effectiveness of light as it's perceived by humans. "Lumens are for humans,” which is ideal for testing household, office and public lighting, but it's a limited gauge for assessing the intensity of horticulture lights. Consumer Interpretation of Lumens Although lumens primarily measures the...

Read more

absorption spectrum, chlorophyll a, chlorophyll b, grow light, horticulture, light absorption, PAR, photosynthesis, zenith LED grow lights -

Part 1, PAR Photosynthesis is the biochemical process by which plants use light to generate fuel and activate various growth mechanisms. The spectral range of light that induces photosynthesis is called Photosynthetically Active Radiation (PAR). PAR is visible light that is measured from 400 to 700 nanometers (nm) and includes Violet, Blue, Green, Yellow, Orange and Red. Of these colors, Violet to Blue (400 to 500nm) is associated with vegetating growth and Orange to Red (600 to 700nm) is associated with flowering growth. Although many plant pigments are not fully understood, the Horticulture Industry has developed a general understanding of...

Read more