Stereo kingfisher is not a species (this is in fact a white-throated kingfisher, which has appeared before on this blog). The image above is a stereo pair – two photos shot from slightly different perspectives, mimicking the binocular vision of the human eye. When viewed through a stereoscope, the pair merges into a single, three-dimensional image.
The same trick – merging into 3D – can also be done with the naked eye. Or at least, some people can do it. The technique is called free-viewing. If you'd like to try and learn, I wrote an article about it for Stereoscopy Blog.
There are special stereo cameras which take two instantaneous photos from different angles. I don't have one, so I use a normal camera. This means I'm limited to 'sequential stereo' – take a photo, move the camera a bit to one side, take another photo. If there is movement between frames, you get a stereo glitch (this post has nice examples; do a text search for 'goth').
Kingfisher with crab is a terrible subject for sequential stereo. The bird was repeatedly bashing the crab against the metal rail (I also took a video, which I will share if I can edit it to my satisfaction). I took at least 20 photos before I got a pair where there was no movement between frames. But what is life without challenges.
Happy equinox, everyone!
