Quote Originally Posted by george013 View Post
I don't think you can resolve lens softness in pp.
In one way you are correct George, once cannot "correct" for lens flaws in an image. What can sometimes be done is to make changes to the image during the post-processing phase that corrects some of these deficiencies. One of the most common ways we do this is by using lens profiles that come with the software. These primarily correct for lens distortions, vignetting and chromatic aberration. The overall effect can be to make the image look somewhat sharper.

When dealing with lens softness, this problem tends to increase as we get away from the centre of the lens, hence all of the comments regarding radial masks and filters. Sharpness in a lens manifests itself as local micro-contrast which is nothing more than enhancing the boundaries between transitions of local lighter and darker areas in the image. One form of micro-contrast that we often see is referred to as "clarity". Using the Unsharp Mask filter and and setting the amount to 20 and the radius to 120 achieves a similar result.

While this approach does not give the identical result to having a sharper lens, it gives a visually similar look, when applied properly.