Marc,

The absolute best way is to duplicate the image. Adjust the contrast. Then use a mask on the modified image and apply it to the original.

basiaclly you are creating a mask on an image that you adjust for easy cropping and applying to the original un altered image.

The eraser tools and wand and all that can be use but many times on the image as is they suck and just waste time.

Once I learned how to work with the same image with better borders it was much easier.

Send me the image and I will cut out if you want.