John Garrett

Collins Complete Photography Projects


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including whether flash is necessary. It is the mode that is recommended for first-time users.

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      P (Program mode)

      The camera is still in automatic but you can override it using exposure compensation and flash. Some cameras will allow flexible program and auto exposure bracketing. This mode is intended for snapshot shooting.

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      S or Tv – TIME VALUE (Shutter priority mode)

      Shutter priority is a semi-automatic setting; you set the shutter speed and the camera sets the aperture for the correct exposure. Use it when the choice of shutter speed is most important for your photograph.

      A or AV – APERTURE VALUE (Aperture priority mode)

      Aperture priority is also a semi-automatic setting, but this time you set the aperture and the camera sets the shutter speed for the correct exposure. This is the mode to set when the choice of aperture is most important for your photograph.

      M (Manual mode)

      Here you are completely in control of both shutter and aperture. You need to use this mode if you want to make long exposures on Bulb setting or shoot with studio flash, where shutter speed and aperture are set independently.

      PRESET SCENES

      The preset programs are the result of an enormous amount of information that has been programmed into your camera. They set up the camera functions to match the subject you have selected, choosing combinations of shutter speed, aperture, flash, colour balance and focus that the camera decides is ideal. These programs are useful when you are starting out, but you will probably want to move on to take your own decisions as your knowledge increases.

      Cameras vary in the style of the graphics and menu for the presets, and in the presets that are available – some offer a wider choice than others. The following are among the most common.

      Portrait mode

      On the assumption that you want the face to stand out from the background by making the background soft, the portrait mode sets the camera to the largest aperture possible in the lighting circumstances.

      Landscape mode

      This sets the camera to the smallest possible aperture that the lighting conditions will allow in order to get as great a depth of field as possible.

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      Close up

      For close up, the camera sets a medium aperture of around f8, depending on available light, to ensure some depth of field to the subject with the background slightly out of focus. It also sets centre focus area. It is advisable to use a tripod, since this preset may give slow shutter speeds.

      Sports

      In order to freeze motion, this mode sets the highest shutter speed that the lighting allows. Focus is set to continuous while the shutter release button is pressed halfway. The built-in flash is turned off.

      Night landscape

      The camera selects slow shutter speeds for night shots. For speeds slower than 1 second, set noise reduction if your camera has it. When using this mode you will probably need to put the camera on a tripod to avoid blur from camera movement.

      Night portrait

      Here the camera balances the flash on the subject with the existing light in the background. You have two choices here: keep the camera and subject still to render everything sharp, or move the camera slightly during the exposure if you want a blurred background. The high speed of the flash will freeze the subject, while the slower shutter speed will allow the background to blur.

      THE ISO SETTING

      Before you start shooting pictures with your camera you must select the ISO setting, either from a button on the camera body or via the menu.

      The ISO (International Standards Organization) index is a system for calibrating the sensitivity to light of film emulsions and digital sensors; the higher the ISO number, the greater the sensitivity. On most cameras the ISO settings go from 100 to approximately 3,200, though the latest digital sensors allow settings of up to ISO 25,000.

      The lower the ISO number, the finer the quality of the image, whether film or digital. As the ISO number rises so does the amount of noise in a digital image and grain in a film negative, breaking up the image and reducing sharpness and detail. Noise reduction can be turned on when shooting at higher ISOs, but it tends to soften the image somewhat. It has no benefit at low ISOs.

      Grain and noise are not necessarily a bad thing – they can be another creative tool, used to enhance subjects such as misty mornings and night shots, for example, and often most effective in black and white shots.

      QUICK TIP

      Try to get into the habit of checking the ISO setting each time before you start shooting or you may end up with a lot of pictures on a setting that does not suit the subject. Remember you can change your ISO at any time during a shoot – for instance, if the light drops suddenly and you find the shutter speed has become too slow for a hand-held camera, just turn up the ISO and retain your higher shutter speed.

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      LOW ISO

      This is a small section taken out of a portrait to demonstrate the quality of image that is possible on a digital camera with a low ISO setting.

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      HIGH ISO

      The section here is proportionally the same size in an image as the eye from the portrait, but the shot has been taken with a high ISO setting. While great effort is made by manufacturers to reduce grain and noise, it can be really attractive on some images.

      EXPOSURE

      For most of our careers, correct exposure was the most important technical decision that we had to make because most of our work was on colour transparency film, and the quality of the image was greatly affected if it was overexposed by even +½ stop. It was safer to be –½ stop underexposed to give a rich, saturated transparency for reproduction.

      Today, photographic technique is equally divided between the camera and the computer, so if you find your pictures are under- or overexposed you can usually correct that later with image-editing software. However, you do still have to be very careful not to overexpose a subject that has inherent bright highlights. As with transparency film, those highlights ‘blow out’ and lose all detail, and you will never retrieve any detail no matter how much you darken the area on the computer.

      Underexposure of a subject with dark areas is not such a problem, as it is possible to retrieve an image underexposed by as much as –2 stops without adding much noise to the shadows.

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      UNDEREXPOSURE

      This picture is underexposed by –2 stops. However, underexposure can often be used for effect – this exposure, for instance, could be used for an evening