Fixing Lens Distortion Problems in Adobe Photoshop Lightroom 3
From the book
From the book
Ever shoot some buildings downtown and they look like they’re leaning back? Or maybe the top of the building looks wider than the bottom. These types of lens distortions are really pretty common, but in previous versions of Lightroom, to fix these types of problems you had to jump over to Photoshop and manually try to tweak your image there. Luckily, Lightroom 3 can not only fix your lens distortion problem, it can often do it automatically (but of course, you can do it manually if you want to, or if your lens isn’t supported).
Step One:
Open an image that has a lens distortion problem (by the way, this feature also automatically corrects edge vignetting problems and chromatic aberrations as well, which I’ll cover later, but here we’re just going to be focusing on geometric distortion). In this case, I’m using a photo taken with a 10.5mm fisheye lens, and while there are third-party plug-ins you can buy to address the fisheye distortion caused by the lens, since it’s now built in to Lightroom, we don’t have to use them (wild cheers ensue!). Take a look at the image shown here, and the rounding of the court (and the word “Bulls”).
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Step Two:
Scroll down to the Lens Corrections panel. You have two options here at the top: Profile (it fixes the problem automatically) or Manual (you fix it yourself). We’ll start with the auto method, so click on Profile, then turn on the checkbox for Enable Profile Corrections. When you do this—Bam!—your image is fixed (look at how it straightened out the image shown here). It can pull off this mini-miracle because it reads the EXIF data embedded into the photo at the moment you took the shot, so it knows which lens make and model you used to take the image (Adobe included lots of camera and lens profiles for popular Nikon, Canon, Tamron, and Sigma lenses. Take a look under the Lens Profile section and you’ll see your lens’ make and model, and the type of lens profile applied). This is pretty amazing stuff if you ask me, and it all happens all in a split second.
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Step Three:
You can tweak the automatic correction a bit by using the Amount sliders at the bottom of the panel. For example, if you thought it removed too much of the distortion, you can drag the Distortion slider to the left a little (as shown here), and it lessens the amount of rectilinear correction it applied to the photo (notice how the foreground area has a little bit of curve back in it, and there’s less distortion around the far-left and far-right sides? You can see more of the backboard, as well). Having this simple slider to tweak the automatic result is pretty handy (and you’ll probably use it more than you think).
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Step Four:
Now, let’s look at another photo. In this case, the image looks bloated (look at the bridge in the middle—it’s bowed), and look how the buildings on the banks look like they’re leaning back. When you turn on the checkbox for Enable Profile Corrections, you’ll find out that nothing happens, and where it would normally list my lens’ make and model, it reads “None.” That’s because for whatever reason, this image doesn’t have any embedded EXIF data (maybe the image was copied-and-pasted into a blank document, or maybe when it was exported from Lightroom, the Minimize Embedded Metadata checkbox was turned on, so it stripped out that EXIF data, or maybe Lightroom just doesn’t have this lens profile in its database). Whatever the reason, you need to help it out and tell it which brand of lens was used, and which lens it was taken with, and then it can apply an automatic correction.
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Step Five:
In the Lens Profile section of the panel, from the Make pop-up menu, choose the brand of lens you shot with (in this case, it was a Nikon, so I chose Nikon). Then choose the type of lens it was shot with from the Model pop-up menu (this was actually shot with the lens the camera came with—called a “kit lens”—which is an 18–55mm lens, and not a particularly good one at that). Lightroom didn’t have a profile for that exact lens, so I chose the closest match (the 18–200mm), and it actually did a pretty decent job fixing the distortion in the image. If you want the exact profile for your lens, you can do a Google search for it, and find it in all of about 10 seconds, because Adobe released a free Lens Profile Creator utility and people are already filling in the missing lenses, and posting them online for free download (you can download the creator and start making your own custom profiles at http://labs.adobe.com/technologies/lensprofile_creator/).
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Step Six:
Once I chose the closest profile from the Model pop-up menu to the lens I had actually used, it tried to tweak the automatic correction. It wasn’t half bad, but it wasn’t right on the money either. I tried dragging the Amount Distortion slider, but it didn’t do enough. That’s when you click on Manual (at the top of the panel) to reveal the Transform sliders. I wound up having to drag the Distortion slider to +23 to remove the bend and bloating from the bridge in the center, but the buildings were still leaning back. To fix that, I dragged the Vertical slider to +25, and that fixed the leaning problem and made the buildings straight (as seen here). By the way, as soon as you move your cursor over the Transform sliders, the grid you see here over the photo appears to help you with lining everything up (particularly helpful if you’re fixing a bowed horizon line, or rotating the photo using the Rotate slider).
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Step Seven:
Look at the image in the previous step, and you’ll see an area above the top of the image that’s filled with gray. That’s because when you use the Vertical or Horizontal Transform sliders, it tilts the plane of the image, and that’s going to leave a gray gap somewhere (depending on which slider you moved). In this case, because we dragged the Vertical slider to the right, that gray gap is at the top of the image, so the photo will have to be cropped. Luckily, that process can be automated now, too. If you click on the Crop Overlay tool (up in the toolbar near the top in the right side Panels area—right below the Histogram panel), it displays the Crop Overlay options below it. Turn on the checkbox for Constrain To Warp and it automatically adjusts the size of the cropping border, so it crops away all the gray junk (that’s the technical term for it, but Adobe would never admit it).
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Step Eight:
All you have to do now is press the Return (PC: Enter) key to lock in your crop, and your image is fixed (as seen here). I included the original image below, so you can see how the bridge was bowed and the buildings were leaning back.
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Note: Since the profile wasn’t available for the particular lens that I used to take this shot, I also tried a few other Nikon lens profiles (from the Model pop-up menu) to see if any of them did the trick. Although this wasn’t taken with a fisheye lens, I tried the fisheye profile anyway, and it worked surprisingly well (though I still had to use the Vertical Transform slider in Manual mode to get the buildings right). Go ahead and give it a try and see what you think.