The light that comes to the earth from the sun consists of short wave length ultraviolet light, visible light and longer wavelength infrared light. The largest fraction of light is actually infrared. Our eyes can see only in the visible light range. Existing side by side with what we take for ordinary visual reality is a parallel reality created by the reflection of infrared light, to which our eyes are insensitive. One can use a filter on a camera to block out all but infrared light and then record images that are created by the reflection of infrared light off surfaces.
One of the technical problems with making photographs using infrared light is that it takes a longer time to make such an exposure. Thus, if you use an infrared filter you usually should use a tripod to steady the camera and avoid motion blur from any small movements of the camera.
I have worked previously with infrared exposures of landscapes and I'm sure that you have seen images such as the one below of the Lemontree... taken yesterday using an infrared filter. Usually these images are converted into black and white photographs as you see.
In these images the green foliage is rendered as white because chlorophyll fluoresces the infrared light. Like the tropics with snow?!
Without the benefit of a tripod I also made a couple of other infrared photographs. One a portrait and the other of shaded leaves in a tree.
What is really cool about this use is that infrared seems to hide imperfections and shows the skin with a smooth porcelain like glow. She was looking almost directly into the sun, as you can see from her eyes, and yet the photograph is not blownout and looks rather intriguing.
Finally this last image was taken under the canopy of a large tree on the beach... again hand-held.
While there is some motion blur, what I really like is how the leaves are rendered in white and the veins and termite trails are shown as black. It produces a great design and an almost abstract take on the tree branch.
It is possible to have a digital camera permanently converted infrared. This then makes it possible to capture this non-visible part of the spectrum just like shooting in the visible range. Here is a site that offers tutorials and a camera conversion service. Should you decide to do a conversion and try infrared, let us know how you like it!