The trick is pretty simple, it uses the camera's ability to control the DOF (Depth of Field) by adjusting the aperture / f-stop settings. Many point and shoot cameras or smart phone cameras do not give enough control over these settings to make this trick work. An SLR camera with a lens that can open up to an f-stop setting of 5.6 or wider would be best.
Here's the trick. Set the camera for Aperture Priority Mode (see your camera's manual if you are not sure how to do that), open the lens up all the way (f5.6 in this example). Focus on the animal though the cage. The farther away the animal is the better, so a zoom lens is really helpful here. Since the wider the fStop setting (again, f5.6, f3.5 or wider) the depth of field becomes very narrow with things farther from the focus point going out of focus. If the animal was at the far end of the cage, when you focus on it, the bars or cage grill that you are shooting through should magically disappear because they are so out of focus you simply can't see them.
Here's an example:
See the cage next to the Tiger? That's what I was shooting through a few feet in front of me at the far end of the cage. I was zoomed in all the way, so it looks like I'm actually inside the cage with the tiger!
Don't believe it? Here's another example:
Even though I can get some good shots with my iPhone camera, this is why I take my DSLR with me when I go anyplace that will have good photo opportunities!
Hope you find this useful.
