Better VFB sharpening layer

The sharpening function of the frame buffer works very badly, it produces strange halos. It would be nice if the sharpening would produce clean results like in Photoshop.

Why sharpen? Sharpening with a large radius (e.g. 50) with low intensity improves the contrast/brilliance. It's like removing haze from Adobe Camera Raw. It gives a brilliance to the rendering and I used this way via Photoshop for almost all my final renderings. My clients appreciate this trick.

Attached an example of the strange VFB sharpening effect.