First, choose your spot
Spot metering is accurate… when you know how it works
On old-fashioned film cameras, spot meter readings were taken from the centre of the frame. If you expect your Nikon D-SLR to work in the same way, you could end up with some very strange and unpredictable exposures indeed. In fact, on Nikons the spot metering area is linked to the autofocus point. This means you have much more control over it… but you also need to be more careful.