Say goodbye to lens distortions
Shooting with a wideangle lens can lead to optical and perspective distortions. DxO’s Viewpoint and Perspective Efex are here to help remove them, so let’s take a look
If you’re a photographer who uses wideangle lenses, you’ll know all about the optical distortions that can become a problem when shooting with them. It’s well known that these distortions happen both due to the lens’s design, and from how you’re using it. After all, not all lenses are created equal, and not all photographers are either.
In terms of the optical distortions that come from wideangle lens design, the main offender can often be barrel distortion, and whether you’re shooting architure, interiors, street or even nature shots with prominent straight lines, like trees or the horizon, it can make pictures look very unrealistic with those lines curving outwards from the centre, and making scenes look twisted and bulbous.
Allied to that is ‘volume anamorphosis’, a distortion that causes objects at the edge of the frame of a wideangle lens to become stretched compared to those in the centre. You’ll have seen this when framing up a street or nature scene with detail in the foreground, wherein those parts of the frame stretch out and look unnatural. And it’s especially troubling when people are framed at the edges of a picture taken on a wideangle lens, as they’ll widen in a way that no one is going to like.
Another offender – this time caused by the photographer’s positioning of the lens – is perspective distortion, also called converging or diverging verticals, or keystoning. This can happen at all focal lengths, but it’s more prominent when shooting wideangle. The obvious example is when framing up on buildings or street scenes. Keep the lens horizontal and the vertical lines will look straight. But if your lens is tilted up or down even slightly – as it often will be to capture an entire piece of architecture into the shot – then the vertical lines of the building will begin to converge or diverge.
This same issue occurs when trying to shoot a flat subject like the side of a building, a window or even a poster. If your camera lens isn’t aimed perfectly flat-on to the subject, then the lines in the object you’re shooting won’t be straight either. This is the reason that photographers shooting things like flatlays or architectural features spend so much of their time looking at spirit-levels!
How to x distortions
Whatever the distortion you’re encountering, the human brain simply doesn’t see the world in that way, so something has to be done if you want your images looking as natural as possible.
As you know, most imageediting software has tools to fix these kinds of distortions, but DxO Viewpoint and
DxO Nik Collection Perspective Efex are dedicated to the process and give lots of variables, plus some other features, making the process very easy, intuitive and ultimately successful.
So let’s see how some of these tools in Viewpoint and Perspective Efex work. Both packages have identical tools and features, which cover automatic and manual optical corrections to control barrel, pincushion and fisheye distortions, and also volumetric controls to balance the size of subjects shot with a wideangle. There are also perspective controls that let you straighten up the lines in a frame, including the horizon, and cropping tools, too. Viewpoint and Perspective Efex don’t offer controls for correcting fringing or vignetting.
Of course, these tools aren’t magic, and they can only work with what they’re given. And whether you’re correcting barrel distortion, or keystoning, they will have to distort the image back to true, and in the process lose pixels. Therefore, if you have a frame-filling subject that needs correction, you may end up losing bits of it.
The only real difference in how these two packages work is how they integrate in your workflow. Both can be used as standalone packages, and plug-ins in Photoshop and Lightroom, but if you have DxO PhotoLab and want to integrate these features with it, you’ll need to go down the DxO Viewpoint route.