How do I fade photo edges to black?

Just use the gradient tool, super easy to use and control

I have tried all of the above: creating a new black layer with various blending options, masking options--none of them creates a smooth transition to 100% K while leaving the unblended area of the image sharp. Is there really no way to accomplish this?

Welcome to the forum.

As mentioned, several ways to do this.

I like a bit of this, and a bit of that, and ending up using a Layer Mask, with the Vignetting in it.

If your initial Image has your subject on the Background Layer, Dbl-click that, to convert it to a regular Layer, and either accept the default Layer Name, or choose something like "Image Layer." Add either a Color Layer (black) below that, or a New Layer, and Fill with black, then just create your Layer Mask, based closely on CurtY's instructions above. One can add a bunch of Filters to that Layer Mask, for different "looks."

The Layer Mask, when you Save as an Unflattened PSD, can be edited and re-edited forever.

Yes, several ways to do it.

Good luck,

Hunt

There are probably many ways.  One simple way would be to make a selecton from the border in a short distance.  The use gradient fill (background to transparent) with background color black.  A little experimenting should give you the results you want.

Try the Layer Style Inner Shadow with Distance set to 0, Black color, Multiply 100%.

See also:  http://forums.adobe.com/thread/852201?tstart=0

-Noel