I'd agree with Heck's advice, and I would test shooting both in single shot mode and continuous mode. I don't know which Nikon you have, but if it is a simpler/older one, it may be that the autofocus is too slow and loses focus between shots, which happens to me all the time ... I have a Pentax *ist DL which as a model came out in 2005 and is considered an entry level DSLR. I have taken many ´panning shots both in single and continuous mode, really it depends on the event and the speed of the subject but sometimes I still think single is teh best, even though you only get one shot. Also, in continuous mode you don't have to burn off all the shots at once, you can take one or two, wait a fraction of a second and taken the next - but as I said it all depends on the subject you are shooting.