Electronic recording of the infrared image:
Building a false colour image in Photoshop

The ability of image manipulation programs like Adobe Photoshop to separate an image into 'channels' - colour separations for example - means that it is possible to combine an infrared black-and-white image with two other channels of colour information derived from a colour image to create a false colour infrared image. Obviously the infrared and colour images must be identical in terms of position, viewpoint, focal length and depth-of-field. One must of course use a tripod and set the camera to manual. Two images are then recorded - one, a monochrome image with infrared alone - the other a full colour, normal, photograph. The images are then loaded into Photoshop. Using the channels feature one then copies the green channel image into the blue channel, the red channel into the green and the infrared image into the red. One should adjust the levels of each channel prior to recombination as the finished 'false colour' image.

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Biomedical applications of infrared photography >