IOP: Controlling light with apertures

This article contains my notes for the IOP course.

  • Exposure control
    • Each f-stops either halfs or doubles the amount of light.
    • Large aperture will give you a background which is out of focus, e.g. f2
    • A small aperture will give you a image with everything in focus
  • Depth of field
    • is influenced by three important factors
      1. how far away your subject is from your camera lens
      2. the aperture
      3. the focal length
  • Spot metering
    • Works by measuring light in only one small spot of the centre of the viewfinder. This cuts out too much light and can lead to more accurate exposure.
    • Good if you have a very light or dark background compared to the subject.
  • Hand-held exposure meter
    • External meter
    • Allows you to correctly place the meter, like correctly placing the thermostat in your house.
  • The sunny f/16 rule
    • Set aperture to f/16
    • Set the shutter speed and iso setting to 100.
    • Adjust as needed.
    • f/16 - sunny
    • f/11 - slightly cloudy
    • f/8 - cloudy
    • f/5.6 - heavy cloud
    • f/4 - sunset
  • Bracketing
    • Taking a few shots with different exposure settings to identify the optimum settings.
    • Auto bracketing does this for you automatically, allowing you to choose later on.
  • Exposure compensation
    • You can set the exposure manually using a technique called exposure compensation.
    • You can set the exposure compensation mount up to +/- 2 stop in 1/2 stop increments.