Softening The Edges Adobe Photoshop / Photo Effects
How good your selection seems to be, sometimes the edges still look a little too "hard" when you look at the object on top of its new background. Here's a simple way to soften the edges of anything on its own layer.
Edge Sharpening Adobe Photoshop / Photo Retouch
Sharpen the edges of a portrait without sharpening the skin. This sharpening technique detects edges and applies sharpening only to the edges.
Transparency Adobe Photoshop / Web Graphics
Learn how to adjust transperent images to get rid of the jagged edges like in the top image and get smooth edges like in the bottom image.