Colour Infrared (IR) Landscape Photography

by

  Bluesky

Infrared (IR) radiation falls into the light spectrum beyond red and is invisible to human eyes. However, some digital cameras can clearly see the light in the near-IR spectral range and display the image seen directly on their LCDs. This makes the digital IR photography possible and much more convenient than the traditional film approach. An IR photograph is usually manifested as monochromatic (B&W) when a true IR filter is used. There are also other IR filters (Hoya R72 is a typical example), which are not so opaque to prevent all visible light from coming into the lens and reaching the CCD or CMOS sensors. The colour processing arrangement and optical system inside a particular digital camera may cooperate well with the R72 filter to possibly generate an interesting special colour effect. Owing to the red light with a relatively long wavelength travelling through the filter, the image straight from the camera has a red or magenta colour cast. These colour components after filtration across the entire image form the basis of colour IR photography. It is fairly easy to set up a custom white balance to clean up the reddish hue. This can be done either on camera during shooting or in a digital darkroom using an image-editing software package such as Photoshop. To shoot in JPEG format is often fine, but to shoot in RAW means a greater level of comfort for adjustments. Of course, this is not "real" infrared. Greyscale is not a "right" look of the world either. Regardless of the historical reason, its ability of evoking atmosphere and its strength on tonal differences have been widely appreciated. By the same token, the use of filtered colours in IR photography also has its value for generating a mystical or otherworldly feeling. Furthermore, the colours of these IR photos are tuneable somewhere between monochromatic and normal. Consequently, the image can be made in such a way to have a restricted range of colours that are partially false and partially true. This means that the photos possess the unique IR features (such as the snowy appearance of the foliage due to its strong IR reflectivity) but also retain a natural colour setting to a certain degree. In other words, there is a dreamy mood with unusual but pleasing nuances to the scene without completely loosing the sense of reality. As a result, a landscape may end up with some dramatic hues and vigorous contrast for visual entertainment. To technically obtain the above effect, appropriate post processing is important. The retouching procedure normally does not require too much time. Levelling is my initial step to tighten things up. To swap the red and blue channels turns the sky back to blue. This is useful because an overly eerie scene may not be desired. Colour balance adjustment is also helpful because, as discussed above, colour fidelity here is no longer the same concept as in the normal colour pictures. Other procedures, e.g., cropping and sharpening, are common to all photographs. After completing the workflow, you might feel quite excited looking at the final version of the photograph - What a pleasant surprise! A regular colour picture records a scene as we see it. It is basically what it is and leaves limited room for imagination. In an IR image, we are not only able to see the effect of the invisible IR light, but also able to create various true or false colours during and after shooting. This approach in balancing realistic and surreal colours should offer an artistic flexibility and adds a further dimension for photographic interpretation. Therefore, the entire process becomes quite interesting and enjoyable.