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How does Exposure Triangle work?

In the world of photography, the exposure triangle is also known as optical steps and it is also referred to by this name. In the simplest language, exposure triangle is the relationship between aperture, shutter and ISO in photography. You can take better photos by knowing how to strike a balance between ISO, aperture, and shutter speed, which are actually the three vertices of the exposure triangle. Changing each of these three variables requires changing at least one of the other variables; that’s why having enough knowledge about this triangle is very important to improve your technique and framing.

Important parameters of exposure triangle

With sufficient understanding of all three parameters of the exposure triangle, the balance between all three sides is carefully and consciously created, and the image is recorded with the right quality and light.

1. Shutter Speed: Actually, it is the time that the light radiation happens on the camera sensor. By doubling the shutter speed or increasing one optical step, the amount of light in the image increases. The reason why we want to use a high shutter speed is the Stop Motion feature, which can eliminate movements such as camera shake or subject movement. A high shutter speed gives the sensor less time to record light, and therefore the exposure of the photo will be weaker. Low shutter speeds deliver more light to the sensor and therefore the result is more exposure of the photo.
2. Aperture: Unlike shutter speed and ISO, which can be adjusted from the camera body, the aperture is controlled through the camera lens. By changing the diameter of the aperture valve in the exposure triangle, the amount of light entering the camera sensor also decreases or increases. The larger the aperture (the smaller the aperture number), the more light enters the sensor; As a result, the light of the image increases. Depth of field is a byproduct of aperture. A closed aperture gives you more depth of field and allows more of the scene to be in focus. Wide apertures will have a much shallower depth of field, which will help you isolate a subject, which is one of the best tools for composing your images.
3. ISO: ISO is the sensitivity of the camera sensor to incoming light. ISO numbers usually start from 100 and range up to 1024000. The higher the number chosen for ISO, the higher the sensitivity of the camera sensor, and the smaller the number, the lower the sensitivity of the sensor. Increasing the ISO will help you work in lower light, but high ISO will often increase image noise and reduce detail. Noise is the result of fluctuations in electrical signals. At low ISO, the scale of the image signal is large compared to the noise, which means that the noise cannot affect your image. When working with high ISO, the image signal is equal to the noise signal, and therefore noise will enter the image.

If we want to briefly summarize the subject of the exposure triangle, we must explain that slower shutter speed, higher ISO and wider aperture all increase the light of the photo, and vice versa, each of them will reduce the light of the photo.