In keeping with our philosophy to never alter the underlying background
layer, we're going to show you how we handle cloning. This is a
task that many people perform on the background - we find it particularly
useful to avoid this for two reasons. We generally use the Clone Stamp, Spot Healing, and Healing tool for cleaning up unwanted artifacts, such as dust and scratches.
Sometimes after cloning, particularly over a relatively large area,
you will notice that you've changed the texture or feel of the area.
It can start to resemble scar tissue rather than a continuous gradation
of grain. If you've done this to the background, you may not be
able to undo your efforts. Even if you haven't closed the file,
losing your history states, often cloning chews up your available
history levels anyway so you don't have access any longer to the
state you want to go back to.
Also, if you inadvertantly clone out something that looks like
dust or a defect when enlarged but is actually some piece of detail
in the image, you may not have a way to put it back into the image.
Our strategy will solve both problems.
The trick is to make a new layer (a "bit" layer, not
an adjustment layer). Don't make a copy of the entire background
layer - while this would work, it will immediately double the size
of your file and is unnecessary. After you've made your new layer,
hit "s" on the keyboard to activate the stamp tool and
make sure that the "use all layers" box is checked. This
will cause you to sample from all the layers but place the sample
only on the active layer (which should be your new layer).
Now when you use the clone stamp, Spot Healling and Healing brushes, it will sample off the
background layer and place the sample on the cloning layer, thereby
overlaying the underlying offending area, which is still there on
your background. If you want to undo some cloning, simply use the
eraser tool to remove the sample from the cloning layer, thereby
exposing the original area underneath. Since the new layer will
typically end up containing only a small amount of actual data,
your file size will hardly grow at all.
In versions CS2 and earlier, remember that with the "use all layers" box checked,
any visible layers will affect your sample. If you have added additional
layers and want to do some more cloning, simply turn them all off
so that only the layers you want to sample from are visible - typically
the background layer only. After cloning, you can make your other
layers visible again. If you are using CS3, you may check the "current and below" sample option and avoid turning off layers above your current one. We usually clone as soon as we open the raw