In this tutorial and three others, we are going to explore the Exposure Triangle. The exposure triangle is the combination of three ways to help light enter your camera: Shutter speed, Aperture, and ISO. These three aspects of photography will help your camera get the correct exposure, while giving you complete control on how you want each final image to look. We will start with each piece of the triangle, then look at how those three pieces work together.
A basic camera is made of a hole for light to enter, and film or a digital sensor to capture the light coming in through the lens. SLR and Digital SLR cameras have a curtain that opens and closes in front of that sensor. Shutter speed is the amount of time that door is open for the light to hit the sensor inside. It is written in numbers that are fractions of a second. For example, 1/2 is 1/2 of a second, while 1/2000 is 1/2,000th of a second. Shutter speeds on DSLRs typically vary from 30 seconds to 1/4,000th of a second and above.
As long as the door is open, light is entering the camera and landing on the sensor. This means that, the longer the curtain is open, the more light will enter the camera and the brighter the image will be. The sensor will capture the image of anything in front of it for as long as the curtain is open. This means that if the subject in front of the camera is moving more quickly than the curtain can open and close, it will become blurry. Subjects that are still can have a slower shutter speed and still remain sharp, while subjects that are moving will need faster shutter speeds to remain sharp. Compare these images below:
How to Use Adjust Shutter Speed
There are two ways to practice using shutter speed on your camera. The first is to use S mode (Nikon) or Tv mode (Canon) on the dial on top of the camera. This mode allows to you speed up and slow the shutter speed down, while making the other adjustments for you to correctly expose your image. To adjust the shutter speed, twist the adjustment dial left and right and see what happens. These are all images I have taken using S mode on my Nikon, explaining why I chose the shutter speed I used in each image.
The next way to change shutter speed is to use Manual Mode (M on Nikon and Canon). This mode gives you complete control over the shutter speed, aperture, and ISO all at the same time. We will go over how to do this is the tutorial that shows you how to use all three of these together. For now, try putting your camera in Manual mode. Twist the adjustment dial and see what happens to the shutter speed and exposure level. Take a few shots to see how the image changes when using different shutter speeds.
What Shutter Speed Do I Use?
When considering where to set your shutter speed, think about how fast your subject is moving. If you are photographing something moving very quickly, like a moving car or child, you will need a fast shutter speed. You can download the exposure guide I have made for you to see at-a-glance how fast your shutter speed should be for different subjects.
When you are proficient at understanding how shutter speed works, you can use are a few extra tips when deciding how fast to set your shutter speed:
- Slower shutter speeds will allow more ambient light to bleed into the image. This can be helpful when photographing lights such as Christmas lights or street lights.
- Your shutter should always be as high as the number of milimeters your lens is set to. For example, if you are using a kit lens of 18-55mm and it is zoomed in completely, at least 1/55 of a second is needed to make sure the image is not blurry. If you have a 200mm lens zoomed in, you need to have a shutter speed of at least 1/200th of a second to keep the image sharp.
If you are interested in learning more about shutter speed and how it works, visit some of my favorite sites to read their take on it:
- Improve Photography – Shutter Speed, Aperture, and ISO
- Capture By Lucy – What is Shutter Speed?
- White on Rice Couple – Principles of Photography: Shutter Speed (Controlling Motion)