Results 1 to 3 of 3

Thread: Iso <100

  1. #1
    Senior Member iND's Avatar
    Join Date
    Jan 2009
    Location
    ST LOUIS
    Posts
    400

    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
    Senior Member
    Join Date
    Jan 2009
    Location
    IL
    Posts
    778
    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
    Join Date
    Jan 2009
    Location
    Boston, MA
    Posts
    3,890
    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.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •