I am a naturist, and I have photographed naturists here in Australia and New Zealand for more than 20 years at resorts, beaches, camping, driving, skydiving and bungee jumping (and before you ask, the last two are a little uncomfortable done nude). My forthcoming project over the Christmas-New Year break is to photograph nudes (both genders) in natural rainforest settings using my Pinhole camera, movement and multi-exposure. And the great thing about all this is the "models" (plucked at random) are (un)dressed the same as me, so they are completely at ease — even those that haven't appeared before my camera.
If you want to be successful with nudists (naturists), you need to get down to their level — that means strip and join them.
Playboy and Penthouse are both absolute rubbish — always have been, always will be. That porn is wowserish, exploitative and degrading, additional to being heavily airbrushed. I prefer to photograph and interact with the real thing without pretention or showy dollying-up courtesy that bloody Photoshop tripe.