Apart from Aperture and Shutter speed, another important variable to complete the triangle is ISO.
What is ISO?
ISO stands for International Organisation for Standardization which refers to your camera’s sensitivity to light. In other term, it controls the amount of light-emitting into your camera making your photos darker or lighter.
Higher ISO = brighter image
Lower ISO = darker image
Recapping back from our Photography Triangle blog, ISO needs to work with the other 2 settings (Shutter Speed and Aperture) to give the overall brightness of the image quality. The lowest ISO of 100 will give a darker image which is ideal for shooting outdoors on sunny days while a higher ISO (1600-6400) will give a brighter image, suitable for shooting indoors with dim lighting.
To sum up, Lower value ISO is better used in well-lit conditions while higher value ISO is recommended for low-light situations. Below is the chart to show the different grain effects of the different ISO levels.
While exploring the different ISO values, take into account the graininess of the image which is sometimes artistically used as an effect in photography. Lower ISO values will give less noise (clearer image) while higher ISO values will give more noise (grainier effect). Experimenting with the different ISO values will let you choose the amount of grain you want. Take into consideration adjusting your aperture as well as the shutter speed in various conditions to increase the clarity of the image. A lot of trial and error needs to be done and strongly recommended to use the lowest ISO value (around 50/100) and increase only when needed to. It will maintain image quality but at the same time a blurry effect.
How to choose an ISO value?
The best way for picking the right ISO settings is similar to choosing a value for shutter speed – using the lowest ISO so that you can get a properly exposed photo, with a fast-enough shutter speed to stop motion and cancel out camera shake, and an F-Stop large or small enough to accomplish the depth of field desired. It may differ from time to time, but it’s best to experiment and explore the different ISO to suit the image well.
Refresh your mind again: