The exposure triangle represents the three variables that determine a photo's exposure: aperture, shutter speed, and ISO. Aperture refers to the opening of the lens and affects depth of field. Shutter speed determines the length of time light hits the sensor and is used to freeze or blur motion. ISO enhances exposure but reduces image quality as it increases. Understanding the relationship between these three elements is key to properly exposing photographs in different lighting conditions.

1. Exposure triangle
Lesson 4
Saleha imtiaz

2. The Exposure Triangle is the
representation of the three variables
that determine the exposure of a
photo. Aperture (it also affects depth
of field), shutter speed and ISO.

3. Stop!
• Understanding what a stop is is key to
understanding the exposure triangle.
• In photography, a stop refers to the doubling or
halving of the amount of light that makes up an
exposure.
• Each photo that we take requires a certain
quantity of light to expose it correctly.
• Adding a stop of light by doubling the exposure
will brighten an underexposed image and
Conversely.

4. Shutter speed
• Shutter speed is the length of time light
is allowed to hit the sensor. It is
measured in seconds. Shutter speed is
probably the easiest of the exposure
triangle sides to understand. To double
the amount of light, we need to double
the time of light entering the camera.

5. • Shutter speed ranges from 1/4000th of a
sec to 30 secs.
• Lesser the seconds, lesser is the light in
your gadget and hence in your picture.
• Shutter speed is changed by simply
moving the sutter speed wheel.

6. • Shutter speed determines
the amount of light the
camera sensor receives.
Combining this exposure
can either blur or freeze
motion.

7. • If you decrease the shutter speed it means you
are increasing the time in which camera takes a
picture and vice versa.
• Long exposure or less shutter speed pictures
(1/80 sec to 30 sec) should be avoided when the
camera is hand held because it increases the
chances of picture going out of focus or blurred.

8. • In sports and such events where
you need to freeze the motion, we
use high shutter speed.
• To capture at dark places shutter
speed is decreased to the
adjustment with the
surroundings.
• Shutter speed is kept low to
capture the motion in the picture
like waterfalls and traffic mostly.

9. Its hard to digest!
That’s why we need to break it in two parts

10. aperture
• The easiest definition for aperture is to say
that it’s the opening of your lens. This
adjustable “hole” in your lens is also called
the diaphragm. If you take a closer look at
your camera’s lens, you should see something
like this:

11. • the lower the number, the wider the aperture.
• This means that your camera aperture
settings will be wide open at a smaller f stop
number, like f/1.4 (usually this is the
maximum aperture of a lens). At higher
numbers, like f/16 or f/22, you’ll get a narrow,
small aperture.

12. • Aperture of the camera is changed by
scrolling the shutter wheel while pressing the
+/- button on the top.

13. Affect on exposure:
• Widen the aperture brighter the picture.
• In darker places you can use the aperture at
1.8 to 2.8 as required by the environment.

14. Affect on depth of the field:
• Increased is the f, increased is the depth of field.
• Aperture at its least gives greater bookah or blur.
• For portraits we use least aperture i.e f/1.8.
• For landscape and group photos we use greater aperture.
• We need to manage exposure through shutter speed and
iso according to our required DOF.

15. ISO:
• While managing the exposure triangle iso is our least
priority.
• ISO enhance the exposure with the cost of damaged
image quality.
• Greater the ISO, more is the light in your picture plus
greater number of grains in your picture.
• Increased ISO= increased grains=rougher picture.
• ISO gives vibrant colors to the picture.

16. Overview: