I have been knocking my head against a wall with this one...using PS 6.

I have a photo that is underexposed which I can fix with levels, curves or just duplicating and changing blending mode to screen. That's not the problem...

Problem is that there are 4 people in the photo and the photo was taken under a bunch of trees (thus the darkness) except on one half of a face there is a sun spot thru the trees, making it very bright. I have tried to use the cloning tool to no avail...using regular brushes or soft brushes...changing opacity, using normal/darken/lighten modes. No matter what I have tried, the end result always comes out blurry and not matched up with the rest of the face very well. I even tried deleting the area and just copying/pasting part of the face that looked right (transforming to fit) and you can guess that didn't work well either.

What am I missing/forgetting/just not doing correctly? I have searched for tutorials but haven't found one that is specific enough to help. Also tried a couple tricks out of "ps book for digital photographers" by scott kelby but the tips either were for the entire photo or darkened it way too much to be realistic.

Does anyone have any suggestions? Thanks in advance for your help!
Laura