Nikon soft­ware

Ge­orge Cairns uses Cap­ture NX-D to re­move lens-cre­ated dis­tor­tions

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Re­move lens-cre­ated dis­tor­tions and colour fring­ing us­ing Nikon Cap­ture NX-D

Af­ter light trav­els through your Nikon’s lens it is fo­cused onto a spe­cific point on the cam­era’s sen­sor. How­ever, the im­age cap­tured via your cam­era’s lens may not be an ac­cu­rate rep­re­sen­ta­tion of re­al­ity due to a va­ri­ety of lens-re­lated fac­tors. Cam­era lenses dif­fer in their man­u­fac­tur­ing qual­ity, and var­i­ous types of lens (such as tele­photo and wide-angle) are prone to cap­tur­ing a dis­torted ver­sion of the sub­ject.

A fish­eye lens cap­tures a very wide field of view, but to do so it dra­mat­i­cally warps the cap­tured scene and make it looks spher­i­cal (see page 42). This is an ex­treme ex­am­ple of lens dis­tor­tion, but all lenses will in­tro­duce some de­gree of dis­tor­tion. A wide-angle zoom zoomed out to its widest point, for ex­am­ple, can add bar­rel dis­tor­tion (see page 112): this causes the im­age to bulge out­wards from the middle (as if it’s wrapped round a bar­rel). When zoomed in, the same lens may in­tro­duce pin­cush­ion dis­tor­tion: this is the op­po­site of bar­rel dis­tor­tion, and causes the im­age to pinch in­wards from the edges (much like the edges of a pin­cush­ion are pinched in­wards).

In ad­di­tion to geo­met­ric dis­tor­tion, lenses can also in­tro­duce arte­facts such as chro­matic aber­ra­tion, where colour fringes ap­pear along high-con­trast edges. Cap­ture NX-D can read a pho­to­graph’s me­ta­data, dis­cover what lens and set­tings were used, and then coun­ter­act any dis­tor­tions and colour fring­ing to cre­ate a more ac­cu­rate rep­re­sen­ta­tion of the sub­ject.

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