Jack, I have always gone with an organised safari specialist, however when I was in Mombasa a little while ago I did organise a safari staying at Voi in Tsavo East. Did involve a bit of a drive but cheap to arrange, there are so many comapnys touting for business. If you want to get the best photo opportunities then you need to organise your trip staying at reputable lodges. I stay at Kicheche Mara Camp in Mara North Conservancy, guides are brilliant and the camp superb. They specialise in photo safaris and will get you the best photo opportunities.