SUMMARY
Martin Castein challenges the common understanding of ISO, explaining it amplifies captured signals and noise, not sensor sensitivity. He notes that while high ISO reduces dynamic range, modern cameras handle noise well, and viewers rarely notice it. Castein suggests that an overemphasis on technical perfection, like eliminating noise, can lead to technically flawless but emotionally empty images. He posits that imperfections can signal authenticity and that photographers often become their own harshest critics regarding noise.
TAKEAWAYS
ISO amplifies existing sensor signals and noise, it does not increase light sensitivity.
High ISO settings reduce a camera sensor's dynamic range.
Obsession with technical perfection, like eliminating noise, can result in sterile images.
Viewers are unlikely to be deterred by moderate ISO noise, unlike the photographer.