Nikon D600 For Dummies

Removing (Or Creating) Lens Distortion

Certain lenses can produce a type of distortion that causes straight lines to appear curved. Wide-angle lenses, for example, often create barrel distortion, in which objects at the center of a picture appear to be magnified and pushed forward — as if you wrapped the photo around the outside of a barrel. The effect is perhaps easiest to spot in a rectangular subject like the oil painting in Figure 11-13. Notice that in the original image, on the left, the edges of the painting appear to bow slightly outward. Pincushion distortion affects the photo in the opposite way, making center objects appear smaller and farther away.

Figure 11-13: Barrel distortion makes straight lines appear to bow outward.

If you routinely notice that your lens produces this type of distortion, try enabling the Auto Distortion Control option on the Shooting menu. This feature, explained fully in Chapter 2, attempts to correct distortion as you take the picture. Or you may prefer to wait until after reviewing your photos and then use the Distortion Control tool on the Retouch menu to try to fix things. I applied the filter to create the second version of the subject in Figure 11-13, for example. Less helpful, in my opinion, is a related filter, the Fisheye filter, that actually creates distortion in an attempt to replicate the look of a photo taken with a fisheye lens. ...