As a photographer you strive to get it “right” at the time of image capture, so that you have little or even no work to do in post-processing. But there are times when it’s just not possible to technically achieve your vision in the field.
Let’s say you want to draw the viewer’s eye to a person, objects or areas in the image by using depth of field techniques. You can create the field of focus by using aperture priority and a large (low number) f-stop with sharp focus on the object you want to stand out. Focus on the object, shoot at f/1.8, f/2.8 or f/4 and you are good to go, right? But this can be difficult or even impossible if you don’t have a lens with you that can give you those large openings (or if you use a lens extender, which makes it even harder). And what if you want more than one sharp or blurred area in the same image?
Photoshop to the Rescue
You can use just about any recent version of Photoshop and many excellent plug-ins to create blurred areas in your images. In Photoshop CS5 for example, use the Gaussian Blur filter with one or more layer masks, then some brushing on the masks–well you know the drill. It’s achievable, but depending on the image, it can take some time and patience to be really accurate.
With Photoshop CS6, Adobe has given photographers some new and great ways to accomplish creative blur effects–both quickly and selectively.