I have a photograph containing a silhouette of bird that's slightly out of focus. The edge is well defined, but feathery. Sharpening gives a reasonable improvement, but I curious whether the wizardry of Photoshop could improve things further. I'm quite new to Photoshop and would welcome some guidance on how this could be done, if anyone is willing.
You can probably use curves/levels adjustment to increase the contrast of the edge to give the appearance of a sharper edge. Since it's a silhouette, you don't have (much) detail to worry about. By making the transition between light and dark as contrasty as possible, the edge should appear sharper.
As far as sharpening goes, I would try a high pass filter for an edge like that.