When carrying out photo restoration and restoring an old photograph quite often pieces of it need to be patched up and healed or cloned. To do this you may just grab the clone brush and clone over, but care and planning with sections can create a neater and more convincing job.
If you need to clone up to an object, it is best to select the object first creating a barrier so that no cloning will go beyond that point. The selection should be based on the sharpness of the image. By this, I mean how sharp or how much in focus the image is. For example, if you blow up an image to 200-300% and see how far the pixels merge or overlap between to objects. It may be in a high-resolution image this is only 1 pixel but in a lower resolution or scan of an old photograph with large grain, it may be 3 or 4. It is this “focus” that your image selection should be based on.
By using the focus you can feather your selection and clone up to that point with a realistic edge that suits the image you are working on. Used in conjunction with the “heal” tool this can be a very good method for avoiding the smudge effect you get when healing too close to sections with contrast. If you haven’t come across this before it is very annoying and this simple technique avoids all the undo and re-cloning you may have repeated over and over not quite understanding why it does it.
Here is a short video tutorial on this topic.
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