Start your Viking journey with Runic Formulas. Main features:. "/>. Odin. Ecstasy, Runes, & Norse Magic. $ 26.95. ADD TO CART. Add to wishlist. Imprint: Weiser Books. Availability: In stock. Book preview. "It was said in the lore and legends of Norse mythology that people who got interested in Odin, the god of hunters, warriors and oracular. If we convert this irradiance into Illuminance then we should follow the conversion equation i.e. Where, K m is the constant which is called maximum spectral luminous efficacy and its value is 683 lm/W. By definition the luminous flux received by unit area of the detector is called Illuminance. Its unit is Lux or Lumen per sq. meter (lm/sq. m). This formula is used in the illuminance converter to convert EV to lx and vice versa. Note that though the Exposure Value vs Luminance and Illuminance Table suggests that it is possible to convert cd/m² directly to lux, this is not the case because lux is used to measure the amount of light that falls onto a surface while cd/m² is a unit to. the image illuminance on the film or equivalent declines as we move outward from the center of the image as a result of the geometric optics involved. The result is a relative darkening of the image toward its borders. If we consider a lens having certain ideal properties, it can be shown that the decline in relative illuminance goes very nearly as. Light intensity is a physical term that refers to the luminous flux of visible light received per unit area . Referred to as illuminance , the unit is Lux (Lux or lx). It is used to indicate the intensity of light and the amount of illumination of the surface area of the object. In photometry , luminance is the density of luminous intensity in.