For portrait photography I use Nikon's Nikkor 80-200mm F2.8 ED lens on my D70s body and Nikon F-80 (film SLR). This lens is designed specifically for portraits, sports and nature photography and it is soft lens compared to even the crappy 150 $ 28-80mm G type lens (which is surprisingly 10 times cheaper than 80-200mm F2.6 ED). When I use it on my D70s this lens loose focal length on the widest end and gain focal length on the telephoto end because digital SLRs have image sensor that are smaller than 35mm frame of film.