THE EXPOSURE TRIANGLE EXPOSURE SHUTTER SPEED APERTURE ISO UNDERSTANDING EXPOSURE EXPOSRURE is one of the most critical elements of photography. There are three adjustable elements that control the exposure: ISO, Aperture and Shutter Speed. (4) ISO The measure of a camera sensor’s sensitivity to light (5) Shutter Speed The amount of time that the shutter is open (11) Aperture The size of the opening in the lens when a picture is taken SHUTTER SPEED • Controls the speed at which the shutter opens and closes • The shutter blocks all light from exposing the film UNTIL you press the button. Then it quickly opens and closes, giving the film a brief flash of light. • You can control the length of time the shutter remains open by setting the SHUTTER SPEED. • It determines how long the shutter stays open. • The longer exposures ( like 1 second ) give much more light to the film than a 1/1000 of a second exposure. So even though the number may look bigger, don't be deceived! (Think fractions….1/2 of a pie is larger than 1/8 of a pie). Longer shutter speeds = more light Shorter shutter speeds = less light WHAT SHUTTER SPEED TO USE • A standard shutter speed is 1/125 or 1/250 of a second – these speeds are appropriate for a normally lit outdoor shoot. • Bright, sunny day/ excessive light – use a faster speed such as 1/500 • Overcast or late afternoon – a slower speed should be used, such as 1/60 • A shutter speed slower than 1/60 of a second should only be used with a tripod LIST OF SHUTTER SPEEDS LIST OF SHUTTER SPEEDS APERTURE • Before light reaches film, it must pass through an opening called an "Aperture". • Like the pupil in a human eye, the aperture on a camera controls light. It does so by closing up to restrict light, and opening to let light in. Smaller F-stop number = larger aperture opening Larger aperture openings = more light exposing film APERTURE • The f stop number indicates a fraction of the aperture opening in relation to the focal length of the lens • Each f stop allows half as much light as the f stop before it The larger the f stop number, the smaller the hole in the lens (example f/5.6 is LARGER than f/22) WHAT APERTURE TO USE • A standard aperture is around f.8 or f.11 DEPTH OF FIELD • The easiest way to understand how to control the zone of focus in a photograph is to remember the following: • Large f/stop number (for example, f/22) = large DOF • Small f/stop number (for example, f/4) = small DOF LIST OF F.STOPS ISO (INTERNATIONAL ORGANISATION FOR STANDARDISATION ) • Is the sensitivity of the film or imaging sensor to light • The ISO is often referred to as ‘light speed’ • The faster the film speed, the higher the sensitivity of the film to light • The higher the number, the higher the degree to sensitivity High ISO = Poor lighting conditions (for example indoors without a flash) DO NOW Please get out your camera and find your ISO/ASA, APERTURE and SHUTTER SPEED. Set your ISO/ASA to 400. Set your APERTURE to f/8. Set your SHUTTER SPEED to 1/250. REFERENCE LINKS https://www.youtube.com/watch?v=hExeyRVLLiU https://www.youtube.com/watch?v=3eVjUrY9a9c
