istockphotos seem to have white backgrounds. I like to remove the
white background, and retain the shadows of the subject.

I don't have any problem capturing the shadows ctrl + alt + ~
invert the selection, then fill with black

So the shadows are in a layer. Now I need the subject in a layer over
the shadows but it can be very difficult to isolate a mask the image
subject as the shadows usually adjoin the image.

Are there any good tricks for the 2nd step.. masking the subject and
not the shadows?

KC