Kruger National Park, my friend. We've stayed at Gomo Gomo Game Lodge, loved it and are returning again this summer. Review (w/pictures) below, if interested.
http://www.tripadvisor.com/ShowUserReviews-g471860-d471911-r114946102-Gomo_Gomo_Game_Lodge-Timbavati_Private_Nature_Reserve_Kruger_National_Park.html
We have also self-drive experience in KNP. However, if you want to really concentrate on your photography, I'd seriously advise you to just go with the private reserves so the professional driver/rangers and spotters and get you in front of the wildlife. Also as good as self-drive is, it stinks when you spot a leopard and struggle to juggle the steering wheel and your 400 mm lens out the window at a funny angle before it disappears into the bush.