You may, or may not be a believer in ghost stories, but either way you should be aware of how easy it is to fake a ghost in a photograph.
Get yourself a few photos to mix up. I just happen to have a Christmas angel figure, and an eye photo from one of the previous posts.
Now that you have something to work with, you can start by fading out the “ghosts”, using the opacity slider for the layers. (click to enlarge to see where the opacity slider is)
Select the Eraser tool and reduce the tools opacity and set the hardness to zero, so you don’t have hard edges. You can also use one of the techniques in my previous post for soft vignette edges.
Work with what you have, or get better starting photos of course.
This isn’t perfect, but, if you manage to do this, then you will have no trouble making more convincing ghosts. Mess with the curves a little so you get bloody or pure white ghosts. So now, the next time you see a “ghost sighting photo”, think about how easy it was to make. Which doesn’t necessarily mean that it isn’t real, but I will believe it when I see it with my own, non-edited, vision.