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Thread: Iso <100

  1. #1
    Senior Member iND's Avatar
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    Iso <100

    If we assume that image quality is better in general with lower ISO.

    Are the newer products with ISO < 100 offering a better image quality at 50 and 25
    Or will they bring in noise like higher ISOs.

    Thanks

  2. #2
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    Some might have to do with the camera. Daniel had a write up on the 40D I think. ISO200 is better than ISO100,and ISO50 is the 100 with some extra math on it. Something like that anyway. Cameras have places in the ISO range that give better S/N than their lower counterparts. It might still be in here unless it got truncated by the move to the new server. It was a good read with a link to a graph.
    Words get in the way of what I meant to say.

  3. #3
    Senior Member neuroanatomist's Avatar
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    Each sensor has a base ISO - apparently, it's 100 for some, 160 or 200 for others. Anything up or down from there is gain applied to the signal, analog gain (or negative analog gain, i.e. attenuation) for the 'native' ISO range, digital gain (loss) for the expanded ISO settings (L, H1, etc.).

    Going lower than the base ISO doesn't really deliver better IQ. The problem with designing a sensor with a lower base ISO (which would have better IQ at that lower base) is that to achieve the higher ISO settings, more amplification would be needed - and that means worse IQ. The industry is trending to higher ISOs, so I don't really expect much of a push downward.

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