Beginner basics: What is ISO in photography?
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In the world of photography, there are several technical terms that can be overwhelming for beginners. ISO is one such term that often confuses aspiring photographers. In this article, we will try to simplify the concept of ISO and explain its significance in digital photography.
What is ISO?
ISO stands for International Organization for Standardization, which sets standards for various industries, including photography. In photography, ISO refers to the sensitivity of a digital camera’s image sensor to light. It measures how much light is needed to create a properly exposed image. In simpler terms, ISO determines the camera’s ability to capture images in low-light conditions without compromising the quality.
Back in the days of film, ISO referred to film sensitivity. It still worked pretty much the same way as today’s modern cameras, in that ISO100, was great for bright sunny days, while ISO1600 or even IS)6400 was more for dark indoor settings or night photography.
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Understanding ISO Settings
ISO is represented by a numeric value, such as ISO 100, ISO 400, or ISO 640. The lower the ISO number, the less sensitive the image sensor is to light, resulting in less noise in the image. On the other hand, higher ISO numbers increase the sensor’s sensitivity, allowing you to capture images in low-light environments but at the cost of introducing more noise.
What is noise?
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So what exactly is noise? Noise in photography refers to the grainy veil that can obscure details and degrade the quality of an image. It occurs in low-light situations or when using high ISO settings, as the camera’s sensor struggles to gather enough light, resulting in amplified noise. Noise can distort colors, reduce sharpness, and create an overall lack of clarity. Often making the images unusable. Noise can also be caused by severely underexposed images, rather than high ISO.
What is BASE ISO?
Many camera manufacturers have base ISO settings, this is the lowest native ISO on that camera (or brand). Why is this important? It gives you the potential to produce the highest image quality, minimizing the visibility of noise as much as possible. Older DSLRs and a number of modern cameras have a base ISO of 200, whereas most modern digital cameras (like my Sonya7RIII) have a base ISO of 100. Google the base ISO for your camera and always try to stick to the base ISO to get the highest image quality. However, that’s not always possible to do, especially in low-light conditions.
ISO200 – Minimal noise even due to low light conditions
ISO and Exposure
ISO is closely related to two other fundamental aspects of photography: aperture and shutter speed. Together, these three factors determine the exposure of an image. While aperture controls the amount of light entering the camera through the lens, and shutter speed determines the duration of the exposure, ISO affects the camera’s sensitivity to light. Balancing these settings is essential to achieve a well-exposed image without overexposure or underexposure.
What ISO should you use?
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The choice of ISO setting depends on the shooting conditions and desired artistic effect. For well-lit environments, such as outdoor daylight, a low ISO setting (e.g., ISO 100 or 200) is suitable. This ensures minimal noise and maximum image quality. In low-light situations, like indoor or night photography, higher ISO values (e.g., ISO 800 or above) can be used to capture brighter images. However, it’s important to note that higher ISO values may introduce noise, reducing the overall image quality.
Modern digital cameras and ISO performance
Advancements in camera technology have significantly improved the performance of higher ISO settings. Many modern cameras can handle high ISO values with minimal noise, allowing photographers to capture quality images even in challenging lighting conditions. However, it’s still advisable to use the lowest possible ISO setting to maintain optimal image quality whenever feasible.
Can you remove noise in post-production?
Of course, it’s not always possible to use ISO100, especially in low-light situations or if you need to increase your ISO to get a faster shutter speed. That is where post-production can help. It can’t always fix every image, but in certain situations, it can help enormously. you can try Lightroom Denoise, Topaz Denoise, Luminar Neo Noiseless AI, DXO Pure Raw3, just to start you off.
A final word on ISO
ISO is a crucial setting in photography that determines the sensitivity of the camera’s image sensor to light. By understanding ISO and its relationship with aperture and shutter speed, photographers can capture well-exposed images in various lighting situations, striking a balance between sensitivity and image quality.