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Film Speed EI, ISO, ASA

  • • Higher is more sensitive; 2X steps:
  • 100
  • 200
  • 400
  • • “Auto” increases speed when it's dark
  • • Sensor signal is amplified, then digitized;
  • more amplification implies more noise
  • • Moderate underexposure increases noise
  • • Moderate overexposure clips highlights

    Notes: