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Infrared Photography - A different perspective Robert Williams Wood USA (1910) “We have changed the way photographs of objects are taken by means of infrared radiation. Introduction They are quite different in appearance than ordinary photographs; their chief peculiarity lies in the intense blackness of the sky and the extreme brilliance of the trees and grass. They resemble snow-covered landscapes and bright moonlight than anything else.” Richard Binhammer Photographer USA “Infrared photography captures the light that the human eye cannot see. The resulting dreamlike view offers opportunities to look at the world we often. take for granted in a slightly different way. It makes us question the textures of reality that are always there but often not touched. Infrared photographs become more than records of location and time – they are an expression of seeing the unseen and moments for reflection.” THE ELECTROMAGNETIC SPECTRUM So what is infrared photography? • Its all about the electromagnetic spectrum and what the human eye can and cannot see. • The eye is capable of seeing wavelengths from approximately 380 to 700 nano-metres on the electromagnetic spectrum. • Waves longer than 700nm fall within the infrared spectrum • Other wavelengths are available • In 1910, Robert Wood, (1868-1955) an American physicist produced the first infrared images. • These images were published in the Royal Photographic Society’s October 1910 Journal. • The photographs exhibit the characteristic whitening of healthy foliage which became known as the “Wood Effect” and it remains one of the distinctive features of many infrared pictures today. History of infrared • Dr Walter Clark (1899-1991) involved in the development of infrared film with Eastman Kodak worked with the US Army photography Air Corps to create infrared – sensitized recording material for aerial surveillance. Infrared photography became, and continues to be a vital tool for modern warfare. • The movie industry used IR film to create day-for-night effects to stimulate moonlight scenes in black and white films and helped to popularise the use of IR film • By 1937 some 33 different types of black and white infrared films were available from manufacturers such as Agfa, Kodak and Ilford and The Times regularly published landscape and aerial infrared photographs. 1960’s • The popularization of infrared photography gathered pace in the 1960s when 35mm false- colour infrared film became available from Kodak. • In the 1960’s the unexpected colours and effects infrared film produced appealed to the psychedelic aesthetic of recording artists such as Jimi Hendrix, Donovan, Grateful Dead and Frank Zappa. Saying goodbye to IR film • In the days of film most conventional cameras could use IR film – both black and white and colour. • Lens filters had to be used to block out blue visible light – different colour and strength filters were used to change effects/alter contrast etc. • Some film acquired almost cult status – the glow often seen on IR images was in fact Kodak High Speed Infrared (HIE) black and white negative film. • It needed to be refrigerated, and loaded and unloaded in the dark. And could scratch easily • By 2007, Kodak announced that it would discontinue its 35mm infrared film, both black and white and colour, due to a decline in demand for the product. • Agriculture - Plants with more chlorophyll will reflect more infra-red. By looking at fields or forests, the plant health of an area can be determind. In large scale agriculture this means locally targeted fertilisers can be used, saving money and reducing pollution • Archaeology - Whilst aerial photography has long been used infra- red can show subtle changes in the health of plants due to the underlying soil depth or other factors, and highlight anomalies which would not be visible with conventional aerial photography. • Art and Antiquities - infra-red light is able to penetrate the top layers Some other uses of of paint. It can be used to document under-painting, and identify IR cameras fakes. • Astronomy –improving images of distant objects in deep space • Covert Surveillance - Military, intelligence, and police agencies use infra-red converted cameras to gather intelligence. • Forensics - Infra-red has the ability to penetrate the top layer of skin and can be used to document latent injuries. Infra-red will also penetrate thin layers of paint and can identify damage, or previous repairs to cars, walls and buildings. • Wildlife Filming - IR cameras provide crisp black and white ‘night vision’ shots, enabling wildlife to be filmed in total darkness without disturbance. • By the 1990s the first commercially available digital cameras were available including Kodak’s DCS-100, based on a Nikon film body, and in 1999 Nikon released the D1, a 2.7 megapixel camera costing some £5,000. • Like all subsequent D-SLRs and digital compacts, it incorporated an infrared blocking filter • Today’s infrared photographers therefore need to use digital cameras adapted to record infrared light either by: Moving to Digital • replacing the camera’s internal hot mirror filter (known as a camera conversion) or • by using an external filter screwed onto the lens • The strength of the filter chosen will determine the style of IR that you can capture e.g 720nm, 850nm • Post-processing is a MUST • To give the image the deep contrast and style required • To provide options for false colours Styles of IR Photography Whether you use an external filter or undertake a camera conversion you will need to make decisions around filter size and the style of IR that you want. • 830nm or Super Black and White –produces brilliant whites and rich blacks , resulting in images of high contrast • 720nm or Standard. This is the most common conversion . Its good for false colour with less colour shift that other choices. It also has great contrast for rich black and white images • 665nm or Enhanced Colour–produces pale yellow leaves and bright skies but with less intense colour than the 590nm as below • 590nm or Super Colour. This choice lets in less visible light but still enough to produce vibrant and saturated colours. Leaves tend to appear bright yellow, while skies photograph blue when channel swopped. • 470nm or Hypercolour – this filter admits the largest amount of visible light alongside IR, often resulting in surreal vegetation colours including pink, red and purple. IR photography using an • Good to get started and see if you like the effects external filter • The most inexpensive way to experiment with IR photography • You attach them directly to your camera lens as per other screw on filters • You will need one for each size of lens you use • Images will require long exposure times (10 to 15 seconds even in full sun) • A tripod • Setting a custom white balance – use green grass to do this • Focusing before putting the filter on – autofocus and manual focus will not work through the dark filter lens. So like using a Big Stopper ND filter • Aperture and shutter speed priority modes do not work well • Start with manual mode; low ISO, aperture of around f/5.6 and 10 second shutter speed and adjust from there. • Expensive option – need a “spare” camera body – once converted you will not be able to use the camera for conventional photography • Need to decide on filter strength at the outset – no going back IR photography by • Need a professional conversion. • But shooting with a converted camera is as flexible getting your camera and easy as shooting with your normal camera, no converted long exposures etc. • White balance will be set as part of the conversion. • The quality of your images will be directly dependent upon the quality of the camera you have converted. • This is the serious option • The sensor then records ultraviolet, visible and infrared Full spectrum light together • Lens mounted filters are then used to limit the range of conversion infrared, visible or ultraviolet light. • Not for the faint hearted!! How things look in Infrared • Infrared light does not behave like visible or normal light • Objects that absorb or allow infrared light to pass through them will appear dark • And objects that reflect infrared light back towards the camera will appear light • That is why a light blue sky appears dark and a bright green tree appears light • An object’s reflectivity can be difficult to know without taking a test shot • In addition you want as much light as possible – especially for nature photography • Noon can be ideal – but do not ignore early morning or late afternoon light which can create more drama • The best time of the year is summer, late spring and early autumn when there is a lot of reflected infrared light allowing greater depth of field and faster shutter speeds. • But depending on the effects you want an IR camera can be used all year round Photography by Simon Weir “Beyond Visible Light – a personal journey into the world of digital infrared photography. “Blenheim Palace” Simon Weir UK Photographer “There is always something unexpected in infrared photography - infrared light ‘sees’ much further than visible light, cutting through haze and pollution and revealing distant detail in the landscape invisible to the naked eye. Clouds take on three-dimensional shapes hanging in a deep black sky and water is ominously dark and cold. Trees and foliage become luminous white demonstrating the “Wood Effect” first discovered in the early 20th century.” Photography by Simon Weir “Beyond Visible Light – a personal journey into the world of digital infrared photography. “Hyde Park” Trees, foliage and flowers • Trees, plants and flowers are among infrared photographers favourite subjects • Plants will show great variation in light intensity and glow depending on species, health and season. • The needles of coniferous trees tend to appear darker because they do not have as much reflectivity as other trees.

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