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APERTURE MODE

• The aperture is the size of the opening in the lens through which light is allowed to pass whenever the shutter is opened – the larger the aperture, the more light passes through.
• A larger aperture (a wider opening) has a smaller f-number (e.g. f/2.0) and smaller aperture (a narrower opening) has a larger f-number (e.g. f/22).
• Aperture is one of the most important aspects of photography as it directly influences the amount of an image that is in focus.
• A large f-number (a.k.a small aperture) would mean that a large distance within the scene is in focus, such as the foreground to the background of the landscape.
  • Large f-number = more in focus (small aperture allows in less light)
• A small f-number (a.k.a large aperture) would produce an image where only the subject is in sharp focus, but the background is soft and out of focus. This is often used when shooting portraiture or wildlife to isolate the subject from the background.
  • Small f-number = less in focus (large aperture allows in more light)

SHUTTER MODE

• The shutter speed, measured in seconds (or more often fractions of a second), is the amount of time the shutter stays open when taking a photograph. The longer the shutter stays open, the more light passes through to the sensor to be captured.
• Short shutter speed if you wanted to freeze a fast moving subject, such as shooting sports, action or wildlife
• Long shutter speed if you wanted to blur a moving subject, for example water rushing over a waterfall (slower shutter speeds will require you to put the camera on a tripod to ensure the camera is held steady whilst the shutter is open)

PROGRAM MODE

• In program mode, you are able to set either the aperture or shutter speed, and the camera will maintain the correct exposure by adjusting the other one accordingly, i.e. as you change the aperture, the shutter speed will automatically change, and vice versa.

ISO

• on a bright sunny day there is a lot of available light = use a low ISO number, such as ISO 100 or 200. This will give you images of the highest quality, with very little grain (or noise).
• low light conditions, such as inside a dark cathedral or museum = A high ISO number, such as ISO 3200