Collins Complete Photography Course. John Garrett

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СКАЧАТЬ Rollei make films in this category which are superb when matched with the manufacturers’ recommended developers.

      Medium-speed films: 100 to 200 ISO Films in this versatile group offer most of the qualities of the slow films in terms of fine grain and high resolution but are not as contrasty. This enables them to produce more shadow detail, which is useful for subjects such as landscapes and portraits. Ilford, Kodak, Fuji, Lucky, Adox, Foma and Rollei all have films in this range.

      High-speed films: 400 ISO This group is the most versatile of all, and the manufacturers have been improving their films continually over the years. Ilford’s 400 ISO film started its life as HP3 in the 1950s, became HP4 then HP5, and has now graduated to HP5+, its latest manifestation in a long and distinguished career.

      Today, all the 400 ISO films can be pushed up to 1600 ISO and beyond. At 400 ISO they reproduce a huge tonal range and can be used for almost any subject, which has made them the universal choice for photojournalists for many years and has also made them popular for landscapes on medium- and large-format cameras. As well as Ilford, Kodak, Fuji, Foma and Rollei all have films in this range.

      

      Ultra high-speed films: 1600 to 3200 ISO These are all push films which can be rated at anything from 200 to 50,000 ISO, according to development time. The more you push them the grainier they become, with increased contrast. Use them for available light pictures and for when you want grain for graphic effect. Ilford, Kodak and Fuji produce them.

      Chromogenic films Designed to be processed in C41 colour chemicals, these films have the advantage that they can be quickly processed with colour negative film in a mini lab. Although the negative looks different, they produce a normal black and white print. They are made by Ilford, Kodak and Fuji.

      Infra-red films These films are like normal black and white films except that they have an extended red sensitivity. Foliage and faces become pure white when infra-red film is used with a deep red filter – to get the greatest effect, use an 87 or 88 Wratten filter to cut off all visible light relative to the infra-red. Exposure readings are difficult, and you will need to do a wide bracket (see p.32). Ilford, Rollei and Adox make infra-red films.

      Digital transfer film This is a transparent film with a surface to accept inkjet printing, allowing you to make larger negatives. Makers include Permajet and Pictorico.

      Colour film

      Transparency films Colour transparency or slide film has been the traditional colour film for both the professional as well as the family slideshow evening. It has been preferred for the highest quality commercial printing. Most of the big transparency processing labs have now changed over to digital work, but transparency film still has many devotees.

      Kodak films start from Kodachrome 64 ISO, the sharpest 35mm fine-grain colour film available. Their Ektachrome range starts from 64 ISO and goes to 400 ISO in steps of 100, 200 and 400 ISO. Kodak also make 64T film, a 64 ISO film which is balanced for use with tungsten light.

      Fuji’s slowest colour transparency film is Velvia 50 ISO, which is highly saturated and has fine grain. Velvia is also available at 100 ISO, along with Astia and Provia 100; the latter also comes at 400 ISO. The Velvia films have a warm colour balance, while Asti and Provia are more neutral. Fuji also provide a tungsten-balanced 64 ISO film.

       Kodak 200 ISO transparency film (left) and Fuji 400 ISO colour negative film.

      Colour negative films There have been great improvements in colour negative films over the last ten years; the colour is more accurate, and the grain is smaller and sharper. Most photographers still shooting colour film are using colour negative, which has the advantage that a print can be made in the darkroom or it can be scanned and used digitally.

      Kodak make a range of Portra professional colour negative films at 160, 400 and 800 ISO. These are available with a neutral colour balance (NC) or with more vibrant colour (VC). They also have a large range of amateur films from 200 to 400 ISO.

      The Fuji Superia range covers 100, 200, 400, 800 and 1600 ISO. These films are warmer in colour and sharper than the rest of their range. The Pro range, from 160 to 400 and 800 ISO, is good for a general range of subjects, while Reala 100 ISO has finer grain and lower contrast.

      Lenses

      The primary function of a lens is to focus the image onto the film or sensor. It also controls the angle of view and houses the aperture diaphragm.

      

      Lenses come with fixed focal lengths (known as prime lenses) or as zoom lenses. The latter are designed to provide many focal lengths in one lens, which reduces the amount of equipment that a photographer has to carry on location.

      The advantage of prime lenses is that they have the largest apertures, allowing you to work in lower light levels without a tripod and to choose a shallower depth of field, which is useful in selective focus imagery. They are also still the best in terms of sharpness and minimum distortion.

      Within these two categories there is a further choice between digital (D) and analogue lenses. The former are dedicated to digital cameras and will not work with film cameras; however, the latter can be used with both film and digital cameras, which means that if you are changing from film to digital you won’t have to go to the expense of buying new lenses.

       Perspective correction lenses are used for eliminating the distortion that occurs when you photograph a tall building from a low viewpoint. The front of the lens can be moved up, down and sideways while the camera remains on the same plane. These lenses are mainly used by photographers specializing in architecture.

      Focal lengths

      While the sensors of DSLR cameras vary, they are approximately two-thirds the size of a 35mm film frame. This means that lenses are effectively increased in focal length by 1.5x, so that, for example, a 50mm lens will become a 75mm lens on a digital camera and a 200mm lens has the effect that a 300mm lens would have on film.

      This means that there is an advantage at the telephoto end of focal lengths but a disadvantage in wide-angle lenses because a 24mm lens on a film camera is only about 36mm on a digital camera. To get a really wide-angle effect you need a 12mm or 14mm lens for digital, of which there are now plenty available.

      Lenses range from an 8mm fisheye right up to 2000mm. There are also some very specialized lenses such as the perspective control lens and macro lens. Today, zoom lenses are used almost universally by most photographers, although some still prefer to work with fixed focal lengths.

      You’ll find that just two lenses, a wide-angle zoom and a medium to telephoto zoom, will cover most situations. Indeed, the majority of people never use anything other than a zoom because cameras are usually sold with a zoom lens included, and they are also the easiest, lightest way to go. However, if you are interested in close-up photography you may want to consider using a fixed focal length macro lens as the quality is superior to that of the macro setting on the zoom lens.

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