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Photographing Nature Back to Home Page This page is not intended to be a manual of nature photography: there are excellent books, web-sites and courses on this subject. These notes are merely a simple introduction to a wide-ranging topic for anyone thinking of trying nature photography. You do not need very expensive and complicated equipment, but some cameras are of course unsuitable. A powerful lens or loupe, X8 to X10, is a useful tool. Use it to examine every slide or negative for poor focus and other faults. Then try to work out the causes. Only by being critical can you improve. In five years’ time you may like a smaller fraction of your pictures than you do now, but the pictures you don’t like then will be better than the ones you don’t like now, and the ones you do like then will be very much better than the ones you like now. Knowledge of your subject is valuable, but going out and trying to get photographs will inevitably lead to increasing knowledge. Looking closely through the viewfinder may reveal things that you might not have noticed, even if you don’t get the picture. Reading books will enable you to start out well informed. One of chief considerations is the size of the thing to be photographed. Objects can range from hills and mountains down to microscopic objects. Since they all have to fit on to the film, the magnification must vary inversely with the size of the object. Magnification affects a very important variable – the depth of field. Perfect focus is obtained only at a single distance, for a given setting of the lens-to-film distance. In practice, there is some latitude, because imperfections in focus can be tolerated up to the resolution of the film and lens, if not more, depending on the subject and the requirements of the photographer. One problem with magnification is that the greater it is, the narrower the depth of field. Many objects are about as deep as they are wide. A mountain which is a kilometre wide may have a base which is a kilometre closer than the peak, but this never troubles the photographer. But a fat spider, photographed at high magnification, can be very difficult. To increase depth of field, you have to stop down the lens. This of course reduces the intensity of light getting through, needing either a longer exposure, or the use of a flash gun or other artificial light. At the microscopic level, the depth of field is exceedingly small. At high magnification, the lens is further from the film than for normal photographs, and the brightness of the image is reduced. This must be allowed for when setting the camera. An automatic camera with TTL metering will do it for you. Note that the type of lens and the distance to the object are not in themselves relevant here – it is the resulting magnification that counts. Whether you increase the magnification by getting closer to your subject or by zooming, the result is the same, smaller depth of field. The reason that everything doesn’t just scale up and down with the size of the object is that the camera stays the same size. Images cannot be reduced in size indefinitely because of the finite resolution of the film, even though the makers of emulsions have produced superb results. You need to be sure of the purpose of an outing. You may feel that going out for a walk and observing is what you really like, with photographs as a bonus. Or you may set out with the sole intention of photographing a particular subject, with other sightings as a bonus. Here are some pages about the photographs in this web site – Back to Home Page |