I really like the way this particular trick photography looks, it was quite easy to recreate something similar to this using photoshop and black and white images. Here are two examples which I particularly liked, they are both very striking.
I started with two black and white images of my face, one looking straight into the camera and the other with my hands covering my face. I noticed on the examples neither of the models are smiling so I tried to look as emotionless as possible.
I then used photoshop to merge the layers, I altered the opacity so that the images merged better.
I like how they turned out however they don't really look like the examples I gave so I tried to recreate them using the images I already had. For me to recreate the examples properly I would have to take my images again because the lighting would need to be different. I woud have to be in complete darkness with a spotlight shining on my face. So although the bottom two images aren't really trick photography they have enabled me to see what I need to do if I wanted to recreate the examples from the top.