When I created this guide, I had just purchased the then-new Canon S2IS. I've loved it these few years, and it's served me well. This guide should apply to most consumer-line Canon cameras.
The next item you're going to need is the Hoya R72 Near-Infrared filter. This filter will block out all light except the near-infrared spectrum. When you get the filter, it'll look almost black. You can get one here: Hoya 58mm RM-72 Infrared Filter
You'll also need a way to attach it to the camera. Lensmate has the best adaptor solution for the S2IS, but you'll have to do some research to see if your camera can support screw-on filters, and what is necessary to do so.
It may also be wise to have a tripod handy unless it is a very sunny day. Since most of the light is blocked out by the filter, much longer shutter times are required.
CREATING THE IMAGE
Attach the lens adaptor and filter to the camera. Ensure that the camera is set to Automatic White Balancing. See the manual for your particular model if you're not sure how to do this. Take a look around and find something interesting to photograph. Know that anything containing chlorophyll will be strangely white, and water is usually nearly black. Experiment with different surfaces to find out how they look in near-infrared. You may be surprised that some ordinarilly dull scene becomes interesting and full of life in infrared.
Now we begin post-processing the image into something more appealing. A workflow is provided for you to follow. Perform each step as indicated below. Clicking on the step number opens an image showing exactly what you need to do.If you don't feel like following the step-by-step instructions provided below, I have created an automated Photoshop action that will perform the transformation for you.
Step 1 - Open the image in Photoshop
Step 2 - Duplicate the background layer
Step 3 - Open the channel mixer
Step 4 - Under the Red output channel, move the Red slider to 0 and the Blue slider to 100
Step 5 - Under the Blue Output channel move the Blue slider to 0 and the Red slider to 100
Step 6 - Use the Auto Levels function on the Background Copy layer
Step 7 - Here we can see the false colors really starting to form and create a pleasing image. Next, create a new Hue/Saturation layer
Step 8 - Reduce the Reds saturation to about -85
Step 9 - Reduce the Magenta saturation to about -45. You can achieve some interesting effects by changing the Hues and Saturations on this adjustment layer, so feel free to play with the values I have provided. Don't worry if the changes appear splotchy, they will be smoothed out a bit in the next step. You can always return to this step to fine-tune your image
Step 10 - Finally, change the Hue/Saturation layer type from Normal to Color. Congratulations, you have processed a new IR image! Notice that the image has a grainy look to it. This is common for infrared images, but can be minimized if you wish by using noise cancellation software such as Noise Ninja or Neat Image
Photoshop Action - This is the Photoshop action that performs the above steps automatically. Most versions of Photoshop will allow you to simply drag the downloaded action into your main Photoshop window. From there you can access the action via the Action Pane, which can be made visible using the Window menu, then choose the Actions menu item.