Okay - A brief introduction to how stereophotography works, in a nutshell.
Hold your hands up in front of your face, kung-fu style, and focus on a point in the background.
Wink one eye shut. Now you will be getting only a 2d (flat) view of things.
Now swap! (eyes, that is.) See how your hands seem to "jump" in space as you wink back and forth?
When you look with both eyes, both of these viewpoints combine to make a 3D perspective. The only reason it doesn't seem so pop out and amazing as you'd think, is simply because your eyes are so used to it.
:
When taking a stereophotograph, I use a camera that has two lenses, set roughly about the same distance apart on the camera, as the eyes are in the face. So when I take a photo, the camera takes two pictures, each set slightly apart from the other.
When I view the result of the pictures - either as two images in a stereoscope, or two slides in a special holder, my eyes think they are seeing the object in the picture in stereo, that is, 3d space. If you remember Viewmaster (TM) slides (those circular discs, with their special "push down the lever to move to the next image" viewers) you would have been getting the same effect. Viewmaster viewers are a kind of "stereoscope". However, because my slides are bigger, I get to see more! Hah! ;)
The stereoscope, or the slide viewer, serves to bring the double image close enough to the eyes to fool the brain into thinking it's looking at just one picture. Polarising glasses have a similar effect for viewing larger, or projected, images. It's another means of fooling the eyes into thinking that there's only one picture in front of it, instead of the overlays of more than one image.
Sadly, as I cannot provide you all with viewing lenses, you'll have to try a third way - good old "crossing the eyes".
Sit comfortably back from your screen, and allow your eyes to relax. If you need help, try holding your finger in front of your nose, and focus on your finger as you move it slowly towards the screen. If things are working right, at some point you should notice an illusion of three blurry pictures where there is really only two. Gradually allow your eyes to drift onto the "middle" image from the tip of your finger, and let it come into focus. It should look (hopefully) 3-d ish!
I have also made, for those who find crosseyed viewing slightly tricky, some animated .gif files as seen above. These consist of two images flickering between each other. It won't be a true 3D experience, but you'll get a sense of shape about them. :)
August Update! With the recent arrival of my Slide Scanner, the improved resolution makes me much happier. :) It means of course, an awful lot of scanning, which may take some time. I am debating at the moment how best to proceed, as I have at least a thousand stereo pairs (ranging from Viking ships to arms and armour, to Archaeological sites in the U.K., to - well - all manner of things really. Even a Penguin, a Puffin, and assorted Peoplery...), probably more. In the interim, do click the image below to enjoy this flicker pic of a lovely Vendel Helmet!...
October Update! Recently returned from a visit to Australia. Limited results in my attempts to do shots from a semi submersible on the Great Barrier reef, and the attempts to photograph bats in flight didn't quite come off this time... Maybe next? ;) But I did get a jolly good Koala. Awake, even!
