Ghostly Effects - 8-Point Garbage Matte

The idea of experimenting with this effect is because it is quite a common sight in the fantasy/sci-fi genre (a genre I will be interested in working in). The original plan was to try and put shimmering into the ghost effect, however, I found that actually creating a believable ghost like persona in the film was actually something that needed more attention.
To create the ghost, I used the same technique that I used for the split screen effect. However, where I used the four-point garbage matte for the split screen; for this test, I used the 8-point garbage matte. The point of this was to refine the shot that little bit more; plus, I was not using the entirety of the shot, I was only using one element of it.
Taking the 8-points of the shot,  I adjusted the frame so you could only see Dan out that one shot. I attempted to refine it as much as possibly, so you could only see Dan. However, 8-points was not enough to make it look believable. I then adjusted the opacity to create the ghost and hoped this would solve the problem. However, it did not as you could see other bits from the shot, such as the stairs, ghosted over the under-laying shot. This ruined the edit, so I decided to go back and do the same thing using a 16-point garbage matte.