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Films for unusual effects .. Special techniques .. How to take the most beautiful pictures .. Photography book

Special techniques

Films for unusual effects

We can get a wide variety of impressive effects by using special films and pushing their speed to the maximum limits.

Among the special films we can count the very fast films 800 ASA and above - and the film sensitive to infrared rays and the (recording) films usually used to record physical phenomena and finally the (light) films used in the art of engraving. The range of effects obtained can be expanded by using special development solutions or filters.

High-speed films allow working with the instant image while maintaining a good depth of field. You can work in very low light and also get grainy images, especially with an effective effect. High-contrast films will give bright and detailed images even if the sky is covered with clouds: for example, a landscape shot in these conditions will have a wonderful negative draft, but you should be careful to increase the aperture value by half a stop to increase the exposure time, in order to reduce sudden changes in contrast.

Recording films have a light-sensitive mixture that only records black and white, eliminating all intermediate gray values: we thus have very contrasting drafts. We can sometimes get the same effect with very light drafts drawn on very contrasting paper.

Infrared films are sensitive to invisible infrared radiation: scenes taken with these films and with a special dark red filter look unrealistic and strange. This effect is especially effective in landscapes because some materials (especially chlorophyll) strongly reflect infrared radiation, while other colors such as blue absorb it almost entirely. In such images the grass and leaves are very light while the blue sky appears black. Infrared films can be used without a filter or with filters of different colours and densities, which gives very special effects. However, since infrared radiation is invisible, it is very difficult to predict the results obtained. The wavelength of infrared radiation is longer than that of the visible spectrum, which requires a slight adjustment in the calibration: modern lenses have a special mark to indicate the extent of this correction. In the past there were a large number of special films, but now we see a uniformity in the style: it is now necessary to control the development, the laboratory methods, the lenses and the filters to obtain different effects from a conventional film. Many photographers (and also manufacturers) prefer one type of film that meets all needs and requirements: perhaps this film will appear one day.

- Fast film in poor lighting

I took this picture in overcast weather with the only light coming in from above: very fast film with a lot of contrast. The picture is of poorer quality than those taken in normal light and on slow film. I used 1000 ASA film here but it is usually exposed to 3000 with good results. In low light the built-in pseudo-photometer does not work so a separate pseudo-photometer has to be used.

Leicaflex 1/30 sec aperture 2.8 Kodak Recording 2475

- Specific tones in low light

To give the picture specific grey values ​​I took this picture at twilight on very fast film. I have sometimes used this film in overcast weather but I increased the exposure time a little and got pictures that are normally contrasting and represent a wide range of values.
Hasselblad 1/30 sec Aperture 5.6 Royal X

- High contrast image

We can get very contrast images, i.e. a special problem of black and white, by using recording films or also using special paper and detectors to extract these images. For this image, I started from a draft or a normal negative image, which I multiplied on (Lite) paper with high contrast and exposed it in the appropriate solution, thus obtaining very deep black colors. You should use paper with a hard gradient or LITE paper when we want to print negatives that are slightly exposed to light and very light.
Rolliflex 1/125 sec Aperture 11 Kodak Tri X

- Infrared effect

Unlike the visible spectrum radiations that are absorbed or reflected by objects, infrared radiations that have longer waves are invisible to the human eye. We can make them visible by using infrared film and a dark red filter that absorbs the visible spectrum.
Leicaflex 1/250 sec aperture 16 infrared film.