- lighting 3 -

On having exposed any photosensitive material, a minimal quantity of light is needed. Not only the existing light that we perceive, due to the fact that the eyes are exquisitely sensitive. Light artificial or mixed with natural light but that has the intensity to do a correct exhibition. Another aspect is the aesthetics of the light, for it it is needed to arrange the sources of artificial light in function to creating an atmosphere, so much in the subject to coming out in photographs like to the environment. If it is a photo, bear in mind that it is an alone shot and only it covers a portion of the space where the subject this one. If it is video or cinema at the time it is necessary to illuminate in function to the displacement of the subject in the scene, and to the continuity temporary space. To read the script. There are formulae in order that the lighting expires in spite of having the sufficient level and that his position with regard to the subject provides the contrast of lighting needed. According to the graph. The principal light is to 45 º with regard to the subject and the light of landfill to the opposite side of equal way. The difference of intensities between both lights produces a contrast that it will have to be calculated with the formula: Contrast of Lighting: CI = L.P + L.R / L.R =
And why not? CI = L.P / L.R. Due to the fact that being between them to 90 º frontal to the subject they were creating a point of major sheen in the area where on they impose. The second formula also is cost in the cases where both lights not on impose, as when the L.P is to Left. Of the subject and the L.R to the right side, to 180 º one of other one. The calculation of contrast will have to be done in units of intensity of incidental light. Footcandles (Fc.). If it does not possess an exposure meter of incidental light in Fc. It will have to turn the values of diaphragm into Fc.