Note: Conversion of physical units to subjective units depends on the relative visibility of different wavelengths, ie certain wavelengths are “more visible” to the human eye than others. Therefore as the conversion between lux and μmol. photons m-2 s –1 is wavelength dependent conversions should be approximated only;

Lumen unit of measurementformula

Morel, A. and Smith, R. C. 1974. Relation between total quanta and total energy for aquatic photosynthesis. Limnol. Occanogr 19:591-600.

NB. In other contexts, these units can be misleading. For example, certain photosynthetic bacteria, utilizing infrared light, will not grow under bright fluorescent lamps which are deficient in infrared; however, tungsten lamps of dimmer appearance, but rich in infrared emission, will support much better growth.

Lumen unit of measurementconversion

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