What is ISO? A Simple Guide for Beginners to Manual Mode
ISO is one of the most important concepts to understand if you want to create better photographs, and ESPECIALLY if you want greater manual control over your camera. Adjusting your ISO speed can save an otherwise unobtainable image...or completely destroy your detail if you don't know what you're doing.
Source : https://creativeraw.com/what-is-iso-simple-guide-b
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