Hello RIman, and welcome to the friendly Camera Labs forum!
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As to your question, that's a tough one. Don't forget to switch to C(ontinuous focus). 3d tracking is newest addition to all the dynamic tracking modes - so it should give you an advantage under specific circumstances. But if I remember discussions on other forums correctly 3d tracking works best with colorful objects - but don't bet your house on it
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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