Page 18 - Learning How to Photograph with your DSLR Camera 2nd Edition Jan 2021

Lesson 3: The Essentials of Exposure

The exposure triangle for beginners is my attempt to make it easier for you to
understand exposure and lay the groundwork for all your future photography.
Understanding exposure is the fundamental building block for your mastery of
photography. This will also make it much easier as we progress and learn to shoot in
manual mode. Manual mode is where you have full control of your camera and where
the real magic happens.

Correct Exposure

Correct exposure ensures preserving details,
brightness, and tone in your subject. We have
all seen underexposed images with dark
shadows with loss of detail in those areas. We
have also seen images that are too bright with
no detail in the highlight’s areas. Exposure is
dependent on three things in
combinations: Aperture, Shutter Speed and ISO,
also known as the Exposure Triangle. Aperture
(A-Nikon, AV– Canon), and Shutter Speed
(S Nikon or Tv Canon) are on the Program
knob while ISO is controlled in your camera
menu. Adjusting only one will affect only one
part of the exposure triangle. In Manual Mode
(M) you could control all 3 independently. Figure 8 Nikon D7000 Program Dial

Definitions for This Topic

▪ Aperture is the opening in your lens that allows light into the camera. Similar to the
pupil of the eye it can close to let less light in or open up to let more light in. The amount
of light through the lens to the camera’s sensor contributes to exposure.
▪ Shutter Speed is how long the aperture stays open to receive light. A long shutter speed
allows in more light, while a faster shutter speed lets in less light.
▪ ISO is the sensitivity of the camera sensor to light. This is like the days of film cameras.
For example, shooting ASA 400 film on cloudy days. The lower your ISO number, the
less sensitive the sensor is to light. The higher the number, the more sensitive the
sensor is to light.

18