High Key lighting focused on shooting a light ratio of 1:1 (having the strobes at the exact same angle and shooting the same aperture), but adding an extra strobe. This extra strobe focuses on the white background with a higher aperture than the other two as it will overpower the background. The use of high key lighting produces images with no shadows. The figure has to be a little closer to the lights than the backdrop.
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Low Key lighting focuses shooting a light ratio of 16:1 (having one strobe and sometimes including reflectors). The use of low key lighting creates a dramatic effect on the figure (chiaroscuro) by having a black background. The position of the figure has to farther than the backdrop. Mostly used in noir films.
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