Selective Exposure in Photoshop

I like using this technique when part of the photograph needs correction and editing the entire image doesn't fix an under or over exposed part of the photograph.

First you need to make a selection of the area that you want to correct. You can do this many ways, like the lasso tool, quick mask or the pen tool. I personally most often use the pen tool for complex selections.

Once you have you selection, save it, and then you can adjust levels, curves or color/saturation. It is a very simple task but can make a world of difference.

Here is a link for a good online tutorial of selective exposure. This uses mainly quickmask.
http://www.photographybb.com/forum/viewtopic.php?f=122&t=6745

Here is a before and after picture. I wanted to adjust the contrast on the paper and make it more crisp.

Before:


After: