Is digital imaging a true photographic technique? This is a debate which has rumbled on since the technology developed. To some die-hards, digital prints produced by computer are beneath the dignity of bona fide photographers, but not to us. Hugh and I have given the term "infra-dig" (pronounce as in pig) a new meaning.
We were converted to digital imaging about three years ago. It allowed us to combine two of our hobbies in one go, but more importantly it drastically converted our photographic printing habits from intensive periods of self imposed exile from family life to a genuine shared and social activity. Hugh and I now chat, listen to music and drink the odd glass of wine at the same time as working on images! We have mastered Adobe Photoshop and have a working acquaintance of a number of other programs. We have achieved high quality straight reproduction of both slide and negative films, repaired spoiled historic family photographic records, and produced a number of creative, dare I say "artistic" individual prints and portfolios. This certainly is photography and I am in no doubt that this activity is in principle no different from the use of special darkroom techniques. We were pleased with our efforts, however until we undertook this project I do not think that we had advanced the art of photography through our labours.
Essentially the project has involved digitally combining a standard colour negative image with a corresponding infra-red black-and-white one. Standard photographic emulsion is sensitive to the visible spectrum of light, whilst infra-red film, with a red filter to eliminate other wavelengths, records light into the infra-red region, which is not visible to the eye. Combining them essentially widens the spectrum of light recorded from a single scene onto one picture. What could be more true to the core principles of photography. The use of the computer and digital imaging software permitted control of how the images were brought together in a way which maximised the contribution of different light wavelengths to the final image. This may sound simple, but for many reasons this has been a exacting project.
Two films, two cameras and two photographers, this was an ideal shared activity. There is no need for photography to be solitary! We are fortunate to have duplicate equipment, but problem number one, it is not possible to expose infra red film using cameras bodies which use infra-red in their film transport system, as did our Canon EOS 100’s. So a classic manual wind on camera outfit was retrieved from long term loan to a friend. Unfortunately this was minus instruction manual which we would have welcomed to inform us how to adjust the focus. It is surprising how out of practice one becomes at manually loading films, especially in the dark! We were secure in our use of Fuji Reala, an all time favourite of mine, but the Kodak highspeed infra-red film was an unknown quantity. This was compounded by our not knowing the correction we should allow for an old red filter which we discovered stored in a cardboard box! Bracketing was definitely the order of the day.
We developed the idea for this project in May, sitting in the garden one sunny Saturday afternoon, surely the ideal time for infra-red photography with glowing white foliage and black, blue skies. We did not anticipate the wettest June and July for many years. This was problem number two, finding sunny slots between work and other family commitments in which to take the photos. We could see the summer slipping away. Fortunately patience paid off and there were a couple of fine days during free weekends. By visiting several sites, boasting ample foliage and worthy stonework, during each outing and by working intensively when we were there, we managed to secure enough basic material. We can report that it is possible to successfully change infra-red film in a black holdall, although nearby picnickers did wonder what we were doing!
We took equivalent photographs, with both films using a tripod. The use of a quick release, made it much easier to exchange camera bodies, without disturbing the set-up. The images had to be exactly the same. From time to time we did accidentally move the tripod, and do not believe that you can remember the angle exactly! It was also difficult to achieve precision when the wind, the sun, walkers, rowers and dogs were all intent on doing their own thing, in our field of view! We bracketed the infra-red film by 11/2 stops each way although we did find that the "right" exposure varied under different conditions and not all infra-red images turned out satisfactorily.
The real test came after the chosen images had been scanned into the computer. Not one of the images could be immediately superimposed exactly, so much for the hard part being over. The main reasons for this were slightly varying focal lengths and varying inherent lens properties. It is very difficult to set different manual zoom lenses on exactly the same focal length and I can now see the relevance of all those test articles, examining the optical characteristics of different lenses. Aberration which is not obvious upon independent scrutiny is very evident on comparison. Wherever the images were out of sync the resultant merged image was jarred and confused, thereby destroying any added value. Many hours were spent scaling, rotating and transforming so that the scanned images could be brought together as exactly as possible. Solid structures could be brought in line exactly but not so for the foliage which often moved with the breeze. From time to time we used the resulting softness or double image as a compositional feature.
The composition of the final picture had been established at the time of the initial exposure. The purpose of any subsequent digital manipulation was not to render this unrecognisable, rather to emphasise or develop certain elements of this composition. Accordingly nothing new was introduced and the original scans were unaltered, except for sizing and the removal of the odd extraneous blade of grass or person. Essentially there were three aspects to the manipulation: securing optimal contrast levels, differential blending of the colour image and black-and-white infra-red image and the emphasis of particular features largely through accenting selected edges. Hopefully this would reveal hidden depths to a view. In many ways this was the most straight forward part of the process.
Once a negative is scanned there is huge potential for actively securing contrast levels which not only bring out all the desired detail but which reflect the chosen mood, hard or soft, high or low key without any loss of data. We made full use of this but found that this was not achieved at the touch of a single button but necessitated an understanding of the fine print of the computer program in use. Use of the layers and masks facility was important to us as this offered the opportunity for different types of blending either of the whole of the frame or parts of it. This was key to the production of these images. When the line is the same, as in these pictures, the results depended upon the base colour, the blend colour and the mode of blending which determines which pixels are affected. By selectively copying and blending different parts of the negatives we were able to develop a distinctive image emphasising those aspects of the scene which had caught out attention. Accenting the edges of these areas served to either contain or further draw out these features. Sometimes it is the billowing glowing trees which form the most important part of the picture, other times it is a coloured detail in the foreground, but the image must be viewed as a whole. Most of the pictures also have either water or stone as a dark, infra-red depleted contrast.
This has been a satisfying but very time consuming and intense project, which I do not think we will be in a hurry to repeat, although I think we are now in a position to identify a good day and the right subject and we might well keep a roll of infra-red in the fridge. Our individual skills and strengths as photographers are actually very different, Hugh being painstaking and uncompromising whereas I have a quicker eye and am more creative and experimental. This project needed both attributes and we contributed and learned in equal measure. We have tried hard to produce a series of images each with sufficient interest for them to stand alone but also to develop a portfolio using a common, and as far as we are aware a novel, approach that we consider uses digital techniques to advance the photographic art form. We call it (pronounce as in fridge) "Infra-Dig"!
Judy Thomas A.R.P.S.
July 1998
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