Can anyone help me with the focal length conversion of lenses for Nikon cameras?
Well first things first FX camera’s have a full-frame sensor so what ever focal length the lens is thats what it will be on the FX (ex. 24-70mm is 24-70mm on a FX camera. DX camera’s have a cropped sensor which is smaller then a FX lens due to the smaller sensor the focal lengths on a lens change and are magnified by 1.5x so a (ex. 24-70mm lens on a DX camera would be 36-105mm) the easiest way to to figure out the the focal length is to divide the focal length in half then add it to the original amount (ex. 24mm – half is 12mm – then add it the original amount 12+24= 36mm)( you could also just multiple it by 1.5 – 24*1.5=36mm) So yes your D90’s 18-105mm lens will actually be about 27-157mm, but that same lens on a D700 would be 18-105mm but on another note won’t be used to its full extent since its a DX lens the opening on the lens isn’t big enough to cover the full sensor of the FX camera’s. To answer your other question not all Nikon camera’s have a built in Auto-focus motor such as
