Nikon 300/4 for wildlife, including birds and birds-in-flight

I am just trying out the Nikon d800 with a nikon 300 f4 lens equipped with a Kenko teleplus pro 300 1.4 tc. It works great in good light at 5.6, making sure your subject is in the focal plane. one plus, my old Canon 5d and canon100-400 and a kenko 1.4 would not autofocus past 5.6. The Nikon and Kenko will give full autofocus. you need a tripod, or monopod for bird shooting, this combination is difficult to hold steady

Nikon D800 Nikon 300f4 with Kenko 1.4tc