28. LENS CORRECTION AND GUIDED TRANSFORMATION

AS YOU START making pictures with your camera, you’ll notice that certain lenses cause distortion and vignetting in the images (Figure 28.1). This is common across different types of lenses, but thankfully you have the opportunity to change and mitigate some of this distortion in Lightroom.

Open the image you want to fix in the Develop module and scroll down to the Lens Corrections panel on the right side of the screen. In this panel you will see a checkbox that says Enable Profile Corrections. When you click on this checkbox, Lightroom will read the image metadata and make some changes to the image based on the make, model, and profile of the lens you used to shoot the image (Figure 28.2).

Adobe is constantly updating these lens profiles so that you can quickly correct distortion and vignetting in your images. If you want to adjust the distortion and vignetting on your own at any point, you can use the sliders down at the bottom of the panel (Figure 28.3).

If you notice that your lens suffers from chromatic aberration, you can remove a lot of that by clicking on the Remove Chromatic Aberration checkbox near the top of the Lens Corrections panel.

If you want to take this correction a step further, click on Manual at the top of the panel, and you will find additional options for increasing or decreasing the distortion and vignetting (Figure 28.4). The Defringe sliders enable you to get rid of different pixel colors on the very edges, something that is very common with chromatic aberration.

If your picture is fairly straight and you just want to make these small distortion corrections, the Lens Corrections panel is a great place to start. However, there are times when your camera is off-center or you’re shooting from a vantage point that is a little too low, and you need Lightroom to do an additional transformation to get rid of any lines that seem to be bending in an odd direction. This is when you would use the Transform panel in the Develop module (Figure 28.5).

Figure 28.1 This image, which I shot in Abu Dhabi, is definitely going to need some distortion correction to straighten it out.

Figure 28.2 Applying corrections based on the lens profile.

Figures 28.3–28.4 Adjusting the lens correction after applying a profile.

Figure 28.5 The Transform panel in the Develop module.

By default, the Transform panel is set to Off and all of the sliders are set at 0. If you click on Auto, Lightroom will perform an automatic transformation by looking at the lines instead of the picture, and will attempt to straighten this information for you (Figure 28.6). To be honest, I find that Auto works best for me more often than not, but there are a couple of different options here that I think that are important to mention.

The Level option will allow you to work with the horizontal elements to straighten the picture. The Vertical correction allows you to adjust the horizontal elements, but will also try to straighten vertical lines for you. The Full option applies horizontal and vertical perspective corrections. Full is the option I use the least because I find that it usually doesn’t work very well.

The newest option in this panel is the Guided transformation (Figure 28.7). This allows you to put a series of straight lines in the picture where you believe the straight lines should be. Simply click and drag in an area that you believe should be straight. In Figure 28.8, for example, I thought that the main tower should be vertically straight, so I drew a line on top of it. Once I placed that line, I drew a secondary line in another area I believed should be straight (Figure 28.9). When I drew the second line on another tower, the image straightened itself out.

Figure 28.6 The Auto option in the Transform panel will attempt to straighten your image based on the lines in the picture.

Figure 28.7 The Guided transformation option allows you to draw lines on the areas you think should be straight.

Figure 28.8 I think the tower in the center of the image should be vertically straight, so I drew a straight line here with the Guided transformation tool.

Figure 28.9 I drew a secondary line on top of the tower on the far right, which should also be straight.

You’re not limited to drawing vertical lines, however. In my example image, I wanted to straighten the wall at the bottom of the image, so I drew a horizontal line across the top of the wall (Figure 28.10).

It’s important to note that you only get to use four lines, so I drew my fourth line across the top of the square structure on the far-left side of the picture (Figure 28.11). This straightened the image horizontally.

Once you’ve straightened the image, you can use the Crop tool to get rid of some of the white areas on the edges that are a result of the transformation (Figure 28.12). In the end, you’ll have a smaller picture, but the elements in the picture will be straight.

The one tip I would leave you with is to just try Auto. You’ll be surprised by how well it can do.

Figure 28.10 I drew a horizontal line across the top of the wall at the bottom of the image.

Figure 28.11 I drew my fourth and final line along the top of the square structure on the left.

Figure 28.12 After the transformation is complete, use the Crop tool to get rid of the white areas on the edges of the picture.