top of page

Understanding ISO: The Key to Perfectly Exposed Photos


What is ISO? ISO is the International Organization for Standardization, which is the governing body that sets the standards for camera sensors' light sensitivity. ISO measures how sensitive your camera's sensor is to light. The lower the ISO number, the less sensitive your camera is to light, and vice versa.

If you're a beginner in photography or want to improve your photography skills, then understanding ISO is crucial.

ISO is one of the three fundamental components of the exposure triangle, including aperture and shutter speed. In this article, we'll cover everything you need to know about ISO, how it affects your images, and how to use it to create perfectly exposed photos.

  1. What is ISO? ISO is the International Organization for Standardization, which is the governing body that sets the standards for camera sensors' light sensitivity. ISO measures how sensitive your camera's sensor is to light. The lower the ISO number, the less sensitive your camera is to light, and vice versa.

  2. How does ISO affect your photos? ISO plays a critical role in the exposure triangle. It affects the brightness and noise levels of your images. The higher the ISO, the brighter your image will be. However, the downside of using a high ISO is that it introduces noise, also known as grain, into your images. In contrast, a lower ISO produces less noise but results in darker images.

  3. How to set the ISO on your camera? Most cameras have an ISO button or menu setting that allows you to adjust your ISO. You can set your ISO manually or use the camera's automatic ISO mode. In manual mode, you'll need to adjust the ISO based on the lighting conditions and the effect you want to create in your photos. In automatic mode, the camera will adjust the ISO for you based on the available light, your aperture, and shutter speed settings.

  4. When to use a high ISO? There are times when you may need to use a high ISO, such as when you're shooting in low light conditions, indoor events, or fast-moving subjects. However, using a high ISO will also increase the noise level in your images. Therefore, it's essential to balance your ISO with other components of the exposure triangle to create well-exposed photos.

Tips for using ISO:

a) Try to use the lowest ISO possible in bright light conditions.

b) Use a higher ISO when shooting in low light conditions, but try to balance it with a slower shutter speed and wider aperture.

c) Consider using a tripod or image stabilization when using a slower shutter speed to avoid camera shake.

d) Be aware of the noise levels in your images and use noise reduction software in post-processing if necessary.


In conclusion, ISO is a crucial component of the exposure triangle that affects the brightness and noise levels of your images. Understanding how ISO works and how to use it will help you create perfectly exposed photos in any lighting conditions. and if you have any questions, please leave them in the comments below.

38 views0 comments
bottom of page