What is ISO in Photography
ISO, in photography, is one of the three fundamental pillars of photographic exposure, along with aperture and shutter speed. The acronym ISO comes from the English "International Organization for Standardization", which is the organization responsible for establishing international standards in several areas, including photography.
Understanding the ISO
ISO is a measure of how sensitive the camera's sensor is to light. In simpler terms, it's the setting that determines how sensitive the camera is to light. The higher the ISO number, the more sensitive the sensor becomes to light, and vice versa. This means that in low light conditions you can increase the ISO to capture a brighter image. However, this can also result in a grainier or "noisier" image, which is a kind of visual distortion.
How to use ISO
On most modern digital cameras, the ISO can be adjusted manually, usually within a range of 100 (low light sensitivity) to 6400 (high light sensitivity), although some cameras allow even higher ISO settings. The ideal ISO setting depends on the lighting conditions. In general, it's best to use the lowest possible ISO that still allows the image to be properly exposed.
In bright light conditions, such as on a sunny day, you can usually use a low ISO, such as 100 or 200. In low light conditions, such as indoors or at dusk, you may need to increase the ISO to 800, 1600, or even higher.
ISO considerations
While increasing the ISO can help capture images in low light conditions, it can also result in a grainier or "noisier" image. This is because increasing the ISO amplifies the signal from the camera's sensor, which can result in distortion. Therefore, it is important to balance the need for proper exposure with the desire to minimize noise in the image.
In summary, ISO is a powerful tool in photography that can help control the exposure of the image. However, like all tools, it's important to understand how to use it effectively and to be aware of the potential downsides of very high ISO settings.