Welcome to part one of our 4 part series of Exposing The Triangle: The Exposure Triangle for Beginners. In these series of lessons, we will dive into the 3 elements of the Exposure Triangle, what they are, how they impact your photography and how to control them.
What is the Exposure Triangle?
The exposure triangle is a fundamental concept in photography that explains the relationship between three key elements that determine the exposure of a photograph: aperture, shutter speed, and ISO.
What are the 3 parts of the Exposure Triangle?
Aperture refers to the opening in the lens that controls how much light enters the camera. It is measured in f-stops, with a smaller f-stop number indicating a larger aperture (more light) and a larger f-stop number indicating a smaller aperture (less light).
Shutter speed refers to the amount of time the camera's shutter is open, allowing light to enter and hit the camera's sensor. It is measured in seconds or fractions of a second, with faster shutter speeds letting in less light and slower shutter speeds letting in more light.
ISO refers to the sensitivity of the camera's sensor to light. It is measured in numbers, with a higher ISO number indicating greater sensitivity to light and a lower ISO number indicating less sensitivity to light.
How does the Exposure Triangle impact your photography?
It is all about Balance when it comes to the exposure triangle. That is, balancing the relationship between aperture, shutter speed and ISO when taking a picture, so that you achieve the correct exposure and/or desired look. For example, a photographer may choose a wide aperture to create a shallow depth of field, a fast shutter speed to freeze motion, and a low ISO to reduce noise in the image. This balancing of aperture, shutter speed and ISO will allow the photographer to get the correct exposure and desired image.
If one or more elements of the exposure triangle were not balanced correctly, the image would not be properly exposed. For example, if the shutter speed was too slow, the image would be overexposed (too much light) and have motion blur. If the aperture was too small, then the image would be underexposed (not enough light). If the ISO was too high, then the image would be overexposed (too much added light) and have added noise (grainy image).
How to Balance Aperture, Shutter Speed and ISO
Thankfully, most, if not all, modern digital cameras have features and settings that correctly expose an image for you. Depending on the shooting mode you are using, the camera will make the correct adjustments.
Program Auto Mode - The camera adjusts aperture, shutter speed and ISO based on shooting conditions to achieve proper exposure.
Aperture Priority Mode - In this shooting mode, the photographer chooses the Aperture value and the camera adjusts the shutter speed and ISO* (if Auto-ISO is on) to correctly expose the image.
Shutter Priority Mode - In this shooting mode, the photographer chooses the Shutter speed and the camera adjusts the aperture and ISO* (if Auto-ISO is on) to correctly expose the image.
*Note about ISO - There is no ISO Priority Mode. Cameras feature a setting called Auto-ISO where the camera decides the correct ISO value based on the aperture and/or shutter speed. In situations where Auto-ISO is off and the photographer controls the value, the camera will do its best to manipulate shutter speed and/or aperture (depending on the shooting mode) to achieve the correct exposure. In some shooting conditions, this is not possible. The camera will usually warn the photographer through some visual or auditory alert that exposure is not correct and additional adjustments are needed.
The final shooting mode to point out is Manual Mode. In Manual Mode, the photographer has total control over aperture, shutter speed and ISO. This mode does take some time to master, as adjusting the settings incorrectly can easily cause under or over exposed images, motion blur or noise. Thankfully, most digital cameras have some sort of light meter built in to the OVF (Optical View Finder), EVF (Electronic View Finder), rear LCD screen or top LCD screen. For the sake of simplicity, the photographer can adjust settings so that the meter's exposure indicator (depending on the camera, it could be a bar or arrow) is centered on the meter. When done correctly, the image should be properly exposed.
Conclusion
By understanding and adjusting aperture, shutter speed and ISO, you can control the exposure of your image and create a range of creative effects in your photography. In the next series of articles, we will touch on each element of the Exposure Triangle in more detail.
.jpg)
Commentaires