I have two good friends who are both rather accomplished at stereo photography. Last year one of them presented me with a Hasbro my3D viewer for iPhone/iPod Touch. Naturally, I had to try my own hand at some stereo images.

You don't need a stereo viewer to see this in 3D (although it helps). If you don't have one, you might be able to see it using the technique I will try my best to describe. If you can see into those 3D pictures that, on first glance, look like random colored dots, you can do this. If it doesn't work for you, don't feel bad as some people just aren't able.

First, push yourself back from your computer screen. If you are too close, it will be physically impossible.

At this point, some people often say, "cross your eyes" but that is not correct. I would say relax your vision and allow the photo pair to separate into two images and drift apart. This is the difficult part because your brain and eyes very naturally want to pull them back into a single image.

Allow the images to drift apart until you see three photos side-by-side-by-side. The ones on the far left and right will appear semi-transparent and the one in the middle is the overlapped part.

instead of this: | L | R | original photo pair
you'll see this: | L | O | R |

where the center image is the right half of the pair as seen by one eye overlapped with the left half of the pair as seen by your other eye. If you can't get the two halves of the pair to drift far enough to overlap completely, you are too close. Try moving further from the screen or shrinking the size of the photo on your monitor. To give you some idea, I can manage it on my iPhone screen by holding the phone about 18 inches from my eyes, but at full size on a 24-inch diagonal monitor, I literally have to stand across the room.

Once you have managed to overlap the photo halves correctly, your brain should in a sense "lock on" and make it easier to hold them that way. At least it does for me. If you've got it right, that center, overlapped image will appear to have depth. In this example, the head pin will look visibly closer than those to either side.

Good luck. I hope this all makes sense and that you are able to enjoy this photo in all of it's 3D glory.