Indeed, ISO for digital cameras is rather an incorrect term, because these days with digital, there is no such thing as 'film speed'. It's just the old fogies that stick to this term.😂 Being digital, the sensor is connected to amplification of the signal! The higher the ISO, the greater the signal = more 'noise'. Film did not have noise, but grain - larger, coarser silver halide crystals, which produce more visible grain.
And a small thing, but these days ISO isn't short for International Standards Organisation, but rather Iso = meaning equal, as from the Greek 'iso'.
That's what some people say now. Even though back in the day of film, it was the 'International Standards Organisation', an international version of ASA. But these terms now belong in the very very distant past - last century!
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