Fixing Edge Vignetting
If you’re looking at a photo and the corners of the photo appear darker, that’s lens vignetting. Generally, I look at it this way: If it’s just the corners, and they’re just a little bit dark, that’s a problem and I fix it. However, sometimes I want to focus the viewer’s attention on a particular area, so I create a vignette, but I expand it significantly beyond the corners, so it looks like an intentional soft spotlight effect. We’ll look at how to fix it here, and in the next chapter, we’ll look at how to add it for effect.
Here, you can see the dark areas in the corners (that’s the bad vignetting). This is normally caused by the camera’s lens, so don’t blame yourself (unless you bought a really cheap lens—then feel free to give yourself as much grief as you can bear). To remove this vignetting from the corners, start by clicking on the Lens Corrections icon (the sixth icon from the left) at the top of the Panel area. In the Profile tab, turn on the Enable Profile Corrections checkbox and Camera Raw tries to remove the edge vignetting based on your lens’ make and model (it learns this from your image’s EXIF data. See page 88 for more on this). If the image still needs correcting, try the Vignetting slider under Correction Amount.
If the automatic way just isn’t working, do it manually by clicking on the Manual tab. In the Vignetting section, click on the Amount slider and drag it to the right until the vignetting in the corners disappears. Once you move the Amount slider, the Midpoint slider beneath it becomes available. It determines how wide the vignetting repair extends into your photo, so drag it to the left to expand the lightening farther toward the center of your photo.