Thermal images pick up the heat signature created by all living creatures. The photos that can come from these types of cameras can be very artistic looking and are fun to create. If you'd like you can create your own thermal imager in about 30 minutes using an old digital camera.
Cut the film negative into two pieces. They should be square in shape and roughly the size of a quarter.
Take apart your digital camera. If it has screws you can use a Phillips screwdriver, otherwise you will need to use a flat edge like a regular screwdriver to do it. You should use an inexpensive camera for this as you won't be able to use it as a normal camera again. A web camera works great for this.
Find the CCD (charged coupler device). This is the device that is responsible for recording the photograph. It will be sitting behind the lens. It is square in shape and will have a red piece of glass or plastic attached to it. This is the infrared filter.
Remove the infrared filter. You will need to gently pry this off using a flat edge. Be careful not to damage the CCD in the process.
Replace the filter with the negative film. Do this adding a little bit of glue to the film and pressing it firmly on the CCD filter. Wait for it to dry.
Reassemble the camera by screwing it back together. If you are using a webcam you will need to glue it back together.
Take a photo with your infrared camera. Do this in a room in complete or near darkness with people or animals inside of it. You will get a picture with shades of green red, yellow and orange.