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Photographer's Note

Tanning is a natural process, whereby the skin creates the brown-colored pigment called melanin, to protect it against the harmful UV rays in sunlight, but operates equally with artificial UV radiation. There are two different mechanisms involved.
Firstly, the UVC-radiation generates oxidative stress, which in turn oxidises pre-existing melanin. This leads to rapid darkening of already existing melanin. Secondly, there is an increased production of melanin (melanogenesis). It is a reaction of the body to photodamage from UVB. Melanogenesis leads to delayed tanning. It first becomes visible about 72 hours after exposure.[1] The tan that is created by an increased melanogenesis lasts much longer than the one that is caused by oxidation of existing melanin.
Darkening of the skin is caused by an increased release of the pigment melanin into the skin's cells after exposure to ultraviolet radiation. Melanin is produced by cells called melanocytes and protects the body from direct and indirect DNA damage absorbing an excess of solar radiation.
The ultraviolet frequencies responsible for tanning are often divided into the UVA and UVB ranges.
(http://en.wikipedia.org/wiki/Sunbathing)

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Additional Photos by Vasilis Protopapas (vasilpro) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 2742 W: 87 N: 5139] (41801)
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