Take con­trol of the aut­o­fo­cus points

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While the fo­cus mode de­ter­mines how the cam­era fo­cuses, the AF-area mode de­ter­mines where it fo­cuses. As with aut­o­fo­cus modes, there’s a trio of core AF-area modes com­mon to the Nikon range. Sin­gle-point AF en­ables you choose any of the avail­able AF points in the viewfinder – per­fect when you want pre­cise con­trol over where the cam­era is fo­cus­ing. Dy­namic-area AF lets you choose from a set num­ber of ac­tive AF points – typ­i­cally 9, 21 and 39/51, de­pend­ing on the cam­era – while Auto-area AF uses colour and face recog­ni­tion to au­to­mat­i­cally fol­low a sub­ject across the ar­ray of AF sen­sors. The more of these there are, the more likely the cam­era will be able to smoothly keep track.

It’s not just the over­all num­ber of fo­cus points that make a dif­fer­ence, but the type of fo­cus points too. Cross-type fo­cus sen­sors are steadily be­com­ing the stan­dard Once con­fined to the sin­gle cen­tre fo­cus point only, the more pre­cise cross-type fo­cus sen­sors are now typ­i­cally dot­ted through­out the AF sen­sor ar­ray. Some sen­sors only of­fer cross-type per­for­mance at cer­tain aper­tures, and you may need a fast lens – one with a large max­i­mum aper­ture such as f/2.8 – in or­der to trig­ger the full com­ple­ment. Some cam­eras also boast ‘f/8’ aut­o­fo­cus per­for­mance, which is use­ful when at­tach­ing a tele­con­verter to a tele­photo lens. A tele­con­verter re­duces the ef­fec­tive max­i­mum aper­ture of the lens, but with f/8 aut­o­fo­cus you can use a 2x tele­con­verter on an f/4 lens and still re­tain the ben­e­fits of aut­o­fo­cus.

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