Uploaded by Ruhma Shazab

Exposure Triangle

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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
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