A Cloning Primer
Use these tips to master the subtle power of the Clone Stamp tool
No matter how hard you try to keep everything looking good in the picture area, sooner or later something creeps in that doesn't belong. Visual trash creates a distraction from your subject and your composition. It keeps you from enjoying your photo as much as you'd like, and every time you look at the image, that junk just seems to taunt you.
Luckily, you can get rid of these distractions with the Cloning tool of any image-processing program—but be careful. Doing visual surgery to an image can create its own problems. Do it wrong, and everyone knows you "Photoshopped" the image. Do it right, and your original intent for your photograph comes through beautifully.
Basic Cloning Procedure
The tool behaves essentially like a Brush tool, which means it's a circular tool that has controls to change the size and softness of the brush, as well as its opacity (how densely it's applied).
Cloning isn't a complicated technique, though it does take a practiced hand to do it well. You'll find that with practice, you'll get better at cloning. Here are the basic steps in Adobe Photoshop CS3; tools and settings may be called by different names in other software, but the steps are basically the same.
1. Enlarge your photo to best show the problem area.
2. Select the Clone Stamp tool from the Tool palette and set its brush characteristics. Choose and set a size that's close to the size of details in the area you want to remove from the photo. Use a soft-edged brush, with the hardness set to 0. For most work, you want to use the aligned setting, which means the clone-from point always stays the same distance and angle to the clone-to point. If you don't use the aligned setting, the clone-from point always will go back to the original set point whenever you click the mouse (which can be useful if you have a very small clone-from area).
3. Clone to a layer. This is an important step. If you clone into the photo itself, you'll have problems making corrections later. If you clone to a layer, you aren't affecting your original pixels and easily can erase parts of your cloning work or delete the layer altogether without permanently changing the original image. To add a new layer, go to the Layer menu and select New > Layer. Be sure your Clone Stamp tool is set to work with all layers (Sample: All Layers).
4. Set your clone-from point by holding the Alt/Option key when you click on the spot. The point you choose to clone from is important. Find something as close as possible in tone, color and texture to the surroundings of the area you want to remove.
5. Try it. Move your cursor over the problem and click. Does the copy seem to fit? If yes, keep cloning. If no, use the Undo command (Ctrl/Cmd + Z) immediately and set a new cloning point. Never accept a cloned action that doesn't look right. It's easier to undo and set a new clone-from point than to try to fix a poorly cloned area.
6. Build up your cloned area in steps. As soon as you see a problem, stop and undo, then set a new cloning point. Change your brush size if necessary.
7. Watch for cloning artifacts. If you see a pattern appearing that doesn't belong to the photo, change your clone-from point and clone into that pattern to break it up.