Lens distortion is something that has always bothered me in my own photography work, yet early on in my development it was something I always simply put up with due to the fact I didn’t realize how quick and easy it was to correct. Lens distortion isn’t always blatantly obvious (depending on the photograph) and you might get away with not correcting it, however it can be a subtle way to improve upon a final image where you have straight lines that don’t quite look straight.
There are different types of distortion: pincushion distortion, barrel distortion, complex distortion, and perspective distortion, for example.
Due to my interest being mainly in natural landscape photography and using wide-angle lenses, I usually have to deal with barrel/complex distortion It is barrel distortion that affects most of my natural landscape photographs straight out of the camera when using a 17-40mm or 24-70mm lens at their widest zooms. Of course, wide angle lenses are very susceptible to perspective distortion also, particularly when photographing buildings and structures with long straight lines, but I will leave that for another article. Telephoto lenses are more prone to pincushion distortion.
Before & After
Here is a simple image of a sunset at Mandurah, Western Australia, that demonstrates barrel distortion. To the left is the before photo, and to the right is the corrected photo after following the instructions below (you can drag the line to the left and right to see the difference). You may also notice the vignette has also been removed by the software.
Ahh, I love a straight horizon line!
Simple guides on how to correct lens distortion
Adobe Camera Raw (ACR)
My personal workflow involves opening up my photographs in ACR and making RAW adjustments in the software before transferring my photos across to Photoshop for more complex adjustments and edits. In ACR there is a tab aptly named ‘Lens Corrections’ where you can check the ‘Enable Lens Profile Corrections’ option and then select which lens you have used (depending on the camera/lens combination the software may automatically select the lens for you). Voilà. The distortion is corrected! You can then fine-tune the correction, however I’m usually pretty happy with the default settings.
While you’re at it you might as well go ahead and click on the ‘Color’ tab besides the lens profile tab and check ‘Remove Chromatic Aberration’ which is another issue that affects wide angle lenses that is very simple to correct.
The Lightroom workflow is similar to the ACR workflow. You will find a tab named ‘Lens Corrections’ in the Develop section of the software where you can check the ‘Enable Profile Corrections’ option and once again, voilà, the distortion is corrected!
Once again, while you’re at it you might as well go ahead and click on the ‘Color’ tab besides the lens profile tab and check ‘Remove Chromatic Aberration’ which is another issue that affects wide angle lenses that is very simple to correct.
SKRWT (iPhone app) [link]
I enjoy posting my photos to Instagram, however I had the same issue with barrel distortion in my iPhone photographs and images sent directly to my iPhone from my Sony a7R via wifi. In the past I would hesitate to post any photos to Instagram where the lines in buildings or horizons weren’t straight. That was until I downloaded the SKRWT app, which allows you to correct lens distortion (and also perspective distortion) in a very user-friendly interface. You can visit their website via the link above for a in-depth tutorial on how to use the app and what sort of features are included.
The app is US$1.99 at the time of me writing this.
If you have any questions or suggestions, or if you know of a different way to correct distortion, let us know in the comments section below.