I can understand how aperture, shutter speed and ISO affect exposure.
What is Exposure
Exposure is "the total amount of light allowed to fall on the photographic medium during the process of taking a photograph."
Exposure is extremely important and should be something you think about when ever you take a photograph. Exposure is a critical element that determines what is actually recorded on film or an image sensor.
Exposure is extremely important and should be something you think about when ever you take a photograph. Exposure is a critical element that determines what is actually recorded on film or an image sensor.
Exposure is tricky. Too much light will "overexpose" your image, too little light will "underexpose"
What Determines Exposure
The "Exposure Triangle"
- F-Stop (Aperture): the size of the opening that the light passes through (smaller f-stop= more light, larger f-stop= more light)
- Shutter Speed: The Length of time that the sensor is exposed to light (slower= more light, faster= less light)
- ISO: The sensitivity of the sensor (higher= more light, lower= less light)
F-Stop (Aperture)
Aperture is the hole through which light enters the camera. The size of the hold can be changed to control how much light is let into the camera. The smaller the aperture, the less light allowed in.
You can think of aperture like it is your pupil. When it is dark out, your pupils open very wide to allow more light in to help you see better. When you are outside, the sun's light causes your pupils to get smaller. This block some of the light out.
The size of the aperture is referred to as an "f-stop." Larger f-stop numbers are associated with a smaller aperture (like f/22). The small f-stop numbers (like f/ 2.8 are associated to a wider aperture.
Shutter speed also controls your "depth of field" of the area of your photo that is in focus. A small aperture will keep most of your image in clear focus. A wide aperture will keep only a small part of your photo in focus. This gives your photo's background that blurry look.
Your aperture controls the exposure (how much light is allowed in) and the depth of field.
You can think of aperture like it is your pupil. When it is dark out, your pupils open very wide to allow more light in to help you see better. When you are outside, the sun's light causes your pupils to get smaller. This block some of the light out.
The size of the aperture is referred to as an "f-stop." Larger f-stop numbers are associated with a smaller aperture (like f/22). The small f-stop numbers (like f/ 2.8 are associated to a wider aperture.
Shutter speed also controls your "depth of field" of the area of your photo that is in focus. A small aperture will keep most of your image in clear focus. A wide aperture will keep only a small part of your photo in focus. This gives your photo's background that blurry look.
Your aperture controls the exposure (how much light is allowed in) and the depth of field.
Shutter Speed
A shutter is a device that allows light to pass for a determined period of time, for the purpose of exposing an electronic sensor to light to capture a permanent image of a scene.
Shutter speed is the length of time that the shutter is open for. A slow shutter speed allows more time for light to enter- allowing more light to enter the shutter. A faster shutter speed does not allow as much time to let light in, giving you less light.
Think of shutter speed like it is an eyelid.
Shutter speed also controls how motion is captured. If you capture a moving subject with a fast shutter speed, it will freeze the action. If you take a photo of that same moving object with a slow shutter speed, your subject will appear blurry.
Shutter speed controls exposure and how motion is captured.
Shutter speed is the length of time that the shutter is open for. A slow shutter speed allows more time for light to enter- allowing more light to enter the shutter. A faster shutter speed does not allow as much time to let light in, giving you less light.
Think of shutter speed like it is an eyelid.
Shutter speed also controls how motion is captured. If you capture a moving subject with a fast shutter speed, it will freeze the action. If you take a photo of that same moving object with a slow shutter speed, your subject will appear blurry.
Shutter speed controls exposure and how motion is captured.
ISO
The ISO setting makes the sensor more or less sensitive to light. The higher the ISO (3200), the more sensitive the camera is to light, which is helpful when there is not much light around, like at night.
Something to note is the higher the ISO, the more "noise" there will be in your image. "Noise" refers to grainy specks that show up on your image. To avoid "noise" it is best to always use the lowest ISO possible. Strive to use an ISO around 100.
ISO controls exposure and image quality.
Something to note is the higher the ISO, the more "noise" there will be in your image. "Noise" refers to grainy specks that show up on your image. To avoid "noise" it is best to always use the lowest ISO possible. Strive to use an ISO around 100.
ISO controls exposure and image quality.
Using the Whole Exposure Triangle
When taking a photo, it is important that you consider all three parts of the exposure triangle (aperture, shutter speed, and ISO) in order to produce the ideal image.
Each setting should balance each other out to achieve just the right amount of light.
Each setting should balance each other out to achieve just the right amount of light.
Here is a Cheat Sheet