color replacement tool trouble

[dstephendesign]

When I use the color replacement tool, sometimes I get a blend of the color I am replacing and the new color and sometimes it works just right. Is there something in my color settings that could be off? If so what should they be? Also, do different pictures (pictures from the web) have different color profiles that I have to change in order to work on them? It seems that pictures off my camera change easily but pics I am working from off the web have the problem. I don't think it's my settings in the tool bar for color replacement tool because I took them right off the tutorial and my PS book.
Any advice is so appreciated.

 

[Hi_Fi_Guy]

Web images have lower resolution and more compression so it is harder for PS to pul out just the area you want. You may have to resort to using the lasso tool to fine-tune your selections.

Good luck,