Infrared photography grew from early twentieth century experiments with emulsions sensitive to light beyond the visible range, was pushed forward by military reconnaissance, and today lives on through converted digital cameras and filters. Its dreamy look, with bright white foliage and dark skies, has stayed popular because it shows a scene the eye cannot see.
Early Experiments
Photographic chemistry was first sensitive mainly to blue and ultraviolet light. Chemists then learned to add dyes that made plates respond to green, red and eventually near infrared wavelengths. In the early 1900s, scientists such as the physicist Robert W. Wood published landscapes made with infrared-sensitive plates and noticed that leaves turned pale and ghostly, an effect later nicknamed the Wood effect.
Wartime Use
The First World War made aerial photography a serious tool for armies, and interest in how different wavelengths record distant terrain grew along with it. Haze, for example, scatters infrared light less than blue light, so infrared-sensitive materials could cut through atmospheric haze for long-distance views. During the Second World War, specialized infrared film was developed for reconnaissance, and it helped analysts tell living vegetation from material that only looked green to the eye.
Film Becomes an Art Medium
After the wars, infrared film reached ordinary photographers. Several well-known black and white infrared films became favorites for landscape and fashion work, and a few color versions gave surreal pink and red foliage that musicians and album designers adopted. Shooting with film brought quirks that fans still talk about:
- A deep red filter was normally used to block visible light.
- Focus had to be adjusted, because infrared focuses at a slightly different distance than visible light.
- Loading and unloading in complete darkness was often advised, since some films were sensitive through the canister.
- Exposure was guesswork, as meters read visible light only.
The Digital Era
Digital sensors respond naturally to near infrared light, so manufacturers place a filter in front of the sensor to block it. That makes unmodified cameras poor for infrared work unless you use a very dark filter and long exposures. Three routes grew up:
- Screw a dark infrared filter on the lens and use a tripod for long exposures.
- Pay a specialist to replace the internal blocking filter with one that passes infrared, known as a conversion.
- Buy a camera that is sold already modified, or use an older body kept just for this style.
Converted cameras allow normal shutter speeds, live view composition and instant results, which removed most of the guesswork film demanded.
FAQ
Is infrared photography the same as thermal imaging?
No. Near infrared photography records reflected light just beyond what we see. Thermal cameras detect heat radiation at much longer wavelengths using different sensors.
Why does foliage look white?
Healthy leaves reflect a large share of near infrared light, so they record very bright. Skies and water absorb or scatter less of it and look dark, creating the contrast typical of the style.
The Short Version
Infrared photography moved from laboratory plates to military tools, then to film favorites and finally to converted digital bodies. The key traits, bright foliage and dark skies, have remained constant across every technology.
