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The best por­trait lenses for Nikon

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Now that our por­trait guide on page 16 has in­spired you to shoot more por­traits, you may be eval­u­at­ing your kit’s suit­abil­ity. Kit lenses are suit­able for a wide range of sub­jects, but alas, por­trai­ture isn’t one of them; with a widest avail­able aper­ture of f/5.6 at the long end of the zoom range, they sim­ply can’t give you the tight depth of field that you re­ally need for por­traits, for blur­ring the back­ground and mak­ing the per­son you’re shoot­ing re­ally stand out.

Even a top-end stan­dard zoom with an f/2.8 con­stant aper­ture can leave you want­ing a lit­tle more when it comes to lim­it­ing depth of field. And while some find a fast tele­photo zoom a vi­able al­ter­na­tive for por­trai­ture (see our Head to head on page 86), the sheer size and weight of a 70-200mm f/2.8 lens cer­tainly isn’t ideal. Yet another op­tion is to go for a ‘por­trait macro’ lens that has a suit­able fo­cal length. But, again, the widest avail­able aper­ture there is usu­ally a still-lim­it­ing f/2.8.

The best por­trai­ture so­lu­tion is to add a fast prime lens to your D-SLR out­fit. For FX (full-frame) cam­eras, the clas­sic fo­cal length of 85mm en­ables you to shoot head-and-shoul­ders or halflength por­traits from a nat­u­ral dis­tance, with­out in­vad­ing your sub­ject’s per­sonal space. If you’re us­ing a DX-for­mat cam­era with a 1.5x crop fac­tor, a ‘nifty fifty’ lens will give you a sim­i­lar ef­fec­tive fo­cal length of 75mm.

There’s a va­ri­ety of 50mm and 85mm por­trait-friendly prime lenses on the mar­ket, typ­i­cally with a widest aper­ture of f/1.8 or f/1.4. Com­pared with the f/5.6 aper­ture of a stan­dard zoom, these have an aper­ture rat­ing that’s 3.33 or four full stops faster, re­spec­tively. Faster shut­ter speeds can be a bonus, es­pe­cially for in­door por­trai­ture or when putting your sub­ject in the shade to avoid the glare of the sun, but it’s the tighter depth of field of­fered by wide aper­tures that’s the main at­trac­tion.

How sharp should you go?

Cor­ner sharp­ness is of lit­tle im­por­tance if you’ll be blur­ring the back­ground of por­traits, and vi­gnetting at wide aper­tures can ac­tu­ally be an added at­trac­tion. Even ex­treme cen­tre sharp­ness might not be highly de­sir­able, as it’ll show up ev­ery wrin­kle and blem­ish. There’s some­thing to be said for a lens that smooths over the cracks at wide aper­tures, to give a more dreamy look to por­traits. Even so, you might pre­fer to cap­ture as much sharp­ness as pos­si­ble in the eyes, and it’s cer­tainly eas­ier to add smooth­ing at the edit­ing stage, rather than try­ing to in­ject some sharp­ness that sim­ply isn’t there.

What­ever your take on im­age sharp­ness in por­traits, the bokeh of a por­trait lens is of­ten more im­por­tant. Bokeh is a sub­jec­tive mea­sure of the pic­to­rial qual­ity of de­fo­cused ar­eas within an im­age, which should be smooth and creamy. The tran­si­tion be­tween fo­cused and de­fo­cused ar­eas should be smooth too. Fast lenses can also be af­flicted with in­creased lon­gi­tu­di­nal chro­matic aber­ra­tions and coma (see jar­gon buster, be­low).

From a bud­get point of view, f/1.4 lenses are typ­i­cally more ex­pen­sive than their f/1.8 coun­ter­parts. The for­ward el­e­ments in a faster lens need to have a larger di­am­e­ter, to let in more light, so faster lenses are big­ger and more ex­pen­sive to man­u­fac­ture. How­ever, the qual­ity of glass and con­struc­tion can still be just as good in ‘slower’ lenses, or maybe even bet­ter. The two Tam­ron lenses on test aim to keep size and weight to eas­ily man­age­able lev­els with a mod­est f/1.8 aper­ture rat­ing, while also adding op­ti­cal sta­bil­i­sa­tion, which is prac­ti­cally un­heard of in por­trait prime lenses.

Faster shut­ter speeds can be a bonus, but it’s the tighter depth of field of­fered by wide aper­tures that’s the main at­trac­tion

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