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Think of this tip as a public service announcement. I’ve seen many questions on how to get Lightroom’s Lens Vignetting slider to work on cropped photos when you want to darken the edges of a photo. See, the vignette (edge darkening) gets added to the original uncropped image – regardless of the crop you’ve applied. It actually kind of make sense. Think of it this way. The Vignetting adjustment wasn’t really added so we could use it to darken edges creatively. It was added to counteract the effects of lens vignetting with certain lenses (especially when shooting wide open). Since you’d only be removing a vignette from the entire uncropped image it makes sense that it works this way. It’s really only later that people started using this creatively. Anyway, currently (as of Lightroom 1.3) there is no way to change this. So if you find you’d like to slightly darken the edges you could always edit the photo in Photoshop. Then click the Filter menu, choose Distort > Lens Correction and use the Vignette settings in there. That said, make sure you ease up on the settings for this. The edge darkening technique looks nice when used sparingly but tends to look too fake when used at too high of a setting.