Kenneth Clark noted that sexuality was part of the attraction to the nude as a subject of art, stating "no nude, however abstract, should fail to arouse in the spectator some vestige of erotic feeling, even though it be only the faintest shadow—and if it does not do so it is bad art and false morals". According to Clark, the explicit temple sculptures of tenth-century India "are great works of art because their eroticism is part of their whole philosophy". Great art can contain significant sexual content without being obscene.
I think, there is a strong difference between pornography and artistic nudity and those should not be viewed as the same.
From Wikipedia on Nude (Art):