Today I learned ISO = amplification of signal:
ISO 100 = 1X amplification
ISO 1600 = 16X amplification
https://i.nostr.build/9iwmBBlKlUd8e4BI.jpg
https://i.nostr.build/NoNcxRLG3Fdl3I6c.jpg
Each step in ISO, 100, 200, 400, 800… is equivalent to a stop of light, like your f-stops. E.g f-11 at ISO 400 is same exposure as f-16 at ISO 800 or f-10 at ISO 200.
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