If they are indeed doctored than the photoshopper was a true artist. Notice on photo three (the uncircumcised model) how the shadows fall perfectly to the right of his penis? There are also no overt signs on those photos where the organs and bodies merge, nor the pigmentation differences and other telltale giveaways typical of photoshopping. Remember these photos were done decades ago.
Not that I'm divulging any secrets, but FuzzyKen is somewhat of a celebrity with regard to the publishing of penis size material and research into penis enlargement. At one time he and the late Gary Griffin were collaborative partners in a number of books. Perhaps he can add his expertise as to the source and authenticity of these photos.