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Are modern sensors "ISO-less"?
  • Are modern sensors usually "ISO-less" in meaning that gain adjustments are done in the digital domain after ADC?

    I was under the impression that there was some sort of analogue gain applied before the ADC, but that's perhaps only true back in the 1990's...

  • 3 Replies sorted by
  • There is no ADC in CMOS sensors the ADC is inside sensor. Each photodiode has its own conversion on chip on pixel. Then the signal is captured and processed directly to mainboard chip. This is why new CMOS sensors have also memory on chip, and not far away even a prossesor on chip.

    On the other hand CCD did need a ADC chip after signal of the sensor, cos it was analog.

    There is no "ISO-Less" on CMOS image, there is allways noise, you could only pick up noise digitaly on post if you capture RAW from sensor.

    i think you are a little confused

  • @endotoxic

    I'm more confused now. :-)

    So in the modern sensor any gain adjustment (ISO level) is done on the digital data?

    Thus the RAW file never have the ISO backed in so to speak?