SEEING RED! INFRARED PHOTOGRAPHY by Doug Spowart

Many workers in black and white photography after solving the basic problems of image- making and printing-making, find themselves searching for methods by which they can create photographs which look unique and different. Often, the eerily glowing highlights, deep black shadows, halated hot spots and super grainy look of infrared film provides just what they are looking for. Readily available through most major photo suppliers is Kodak High Speed Infrared and Ilford SFX film both of which sell for around $12~14 (Aust). Not as readily available in some countries is the Konica 135mm and 120 roll films.

As Kodak High Speed Infrared film is not manufactured with an anti-halation backing, the grey to very dark backing present in most films, there is a problem with what is called light piping where light enters the cassette via the film through the protruding tongue. This light piping causes significant fogging of the film, evidenced as a vertical band of black on the negative which can extend quite a way through the film. For this reason the High Speed Infrared film cannot be removed from its can, loaded or unloaded in normal light. These functions can only be carried out in complete darkness. A darkroom is not always available so a changing bag can suffice. Practice may be necessary to ensure that you can successfully load your camera in the dark. It is worthwhile noting that the lack of the anti-halation backing on Kodak film provides the interesting halo effect around highlights that are a desirable feature of infrared images. Konica and Ilford films do have an anti-halation backing and can be loaded and loaded in sunlight. Due to the backing on these films the halation effects seen in Kodak film are not as pronounced.

Care must also be taken with the focusing of the camera lens as infrared light comes into focus beyond the focal plane formed by the visible light by which the camera lens is focussed. Most lenses feature an infrared focus mark, usually a red notch or in zoom lenses a red lines. The infrared focus mark enables the photographer to carry out the usual visual focus which is then re-positioned opposite the infrared mark. Re-focusing in this way is vitally important with normal to telephoto lenses, however due to the depth of field characteristics of wide angle lenses in the high aperture range like f11 and f16 no adjustment is required. Autofocus camera users will obviously need to switch to manual focus.

It is often stated that in certain situations of high temperature the film can become sensitive to heat which supposedly results in fog and a reduction of latent image retention. For this reason some workers wrap their cameras in aluminium foil and carry them in styro-foam coolers. I find both procedures unwieldy and unnecessary. In many journeys to very hot outback Australia, even at times when the temperatures have been in the high thirties, I have not had any significant image loss. In my early work with this film in the outback I felt I had to process the day's exposed films each night and hang them out on a tree branch under the stars to dry. But now I bring them home and process them. Other rumours I have heard relate to the film¹s sensitivity to security X-rays at airports. My experience in travels to Africa, China, Japan and New Zealand is that even after multiple passes through X-ray security machinery there is no adverse effect. My procedure for handling airport security is to just let the film go through the system. If however I was using ISO 1600 or 3200 films or was expecting to encounter many passes, 10 or more I would request a hand search. [Please Note : There are concerns about new X-ray machines that have come into service recently that may have a greater potential to create an exposure on film ~ My current advice, until tests can suggest otherwise is to always request hand searches]

Most infrared films are essentially panchromatic emulsions (ie. sensitive to all colors of light), with extended sensitivity into the infrared light region. Shooting pictures without removing most of the visual spectrum would result in pictures which look almost normal and lacking the characteristic false tonal reproduction effect desired. As such a number 25A red filter is specified by the manufacturer, other filters including infrared transmitting only filters (Series 87 & 88) can be used and may provide some interesting results through experimentation. The major problem with infrared light transmitting only filters is that they are opaque creating real problems for the SLR user and exposures are generally much longer which necessitates the use of cumbersome tripods and cable releases. Whilst filtering is normally used with infrared film it can also be successfully used without any filter. The speed may vary depending on the light source used but starting points could be 400~1000 ISO. The results appear not much different to ultra high speed grainy type films, some halation and irradiation occurs in contrasty subjects.

Determining the correct exposure does cause beginners in infrared photography a huge amount of difficulty. As the film is sensitive to wavelengths of light not seen by us or the camera's exposure meter, it is usually quite difficult to gauge correct exposure. The subject's infrared reflectivity can also be misleading and cause problems. Generous bracketing of exposures is always the best procedure using a ISO meter setting of around 400 (for a 25A Red filter) and the camera's through-the-lens metering system. A bracket two stops either side of the metered exposure should cover most situations. As you gain experience you can begin to get a feel for exposure. I usually guess.

Suggested exposure starting points for different situations is;-

Bright sun ~ 1/60th at f16.

Light cloud ~ 1/60th at f16.

Heavy cloud ~ 1/60th at f8.

Raining ~ 1/60th at f5.6.

Indoors, bright tungsten light ~1/30th at f4.

Indoors, fluorescent light ~ 1/4 at f4.

Konica and Ilford films from my experience may be about 3 stops slower. But do carry out tests.

With Kodak film some care needs to be taken in relation to cameras that have textured or dimpled pressure plates as the patterning of the plate will appear on the film due to light passing through the film and then being bounced back due to the absence of an anti-halation backing. Pressure plate patterns can sometimes add to the aesthetic appearance of the image and therefore it's uniqueness to a particular photographer and their camera. Other unusual problems with infrared film relate to the 'film end' sensing devices used for re-winding film in some Canon cameras. This sensor emits a minuscule amount of light which does not effect normal type films however the effect on infrared is substantial with about a third of the image area being adversely effected.

Processing is easily accomplished using standard procedures and techniques following the data supplied with the film. A little over-development can be helpful in punching-up the contrast. The negative has quite a different look to it from normal continuous tone emulsions. Shadow areas can be quite clear and devoid of detail. Highlights flare out loosing important information. Printing does present some problems as a great deal of skill is often required to get the most out of the unusual negative. Normally higher contrast grades are required and always some tricky dodging and burning-in to fit the negative to the paper. When long burn-in times are required if I'm using variable contrast printing papers I have found it easier to use a lower contrast grade of filter. Konica films exhibit a very high base density which at first looks quite disastrous. However longer enlarger times print through this fog.

Although I am very methodical in photographic procedures and well versed in the technical side of the craft, my experiences with infrared photography, as are also the experiences of many of my students, is that in the beginning everything goes wrong. Many films unexplainably just don't work out. Frustration runs wild. It is as if there is some mystical mischievous gremlin at work to stalk those trying out something new. Perseverance and enthusiasm does always win out! And what of the advice of others? Be careful, it is worth remembering that some accomplished infrared workers may tend to try to protect the niche that they have made for themselves by making infrared photography sound incredibly difficult. Well the secrets out - it isn't it!

Doug Spowart

© March 18, 1997 [modified May Y2K]