A&P why do you need varible 'iso' and 'shutter speed'

Discussion in 'Lifestyle' started by smell my finger, Jul 23, 2004.

  1. smell my finger

    smell my finger strive nonetheless towards beauty and truth,

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    especially on a digital camera.

    as i understand it, iso refers to the sensativity of film to light, and shutter speed determins how much light is let into the camera. now why couldn't these two functions be combined into a single 'light source' type number for simplification?
     
  2. Kinks

    Kinks Sup. OT Supporter

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    because it reduces your flexibility.. it's good to be able to control both.

    However, the D70 will do auto-iso where you set a threashold. Therefore it'll stay until ISO200 until the shutter speed drops below your threshold and then it'll bump up the ISO to maintain your desired minimum shutter speed.

    In general, you get cleaner, less noisy photos with lower ISOs. On film, the grain of higher ISOs can be attractive so it's basically an artistic choice the photographer has to make. You wouldn't want to eliminate that choice.
     
  3. donnyhall

    donnyhall Guest

    ISO has a lot to do with desired effect and or condition.

    [font=arial,helvetica][size=-1]Film comes with an ASA (American Standards Association) or ISO (International Standards Organization) rating that tells you its speed. The ISO and ASA scales are identical. Here are some of the most common film speeds:
    • ISO 100 - good for outdoor photography in bright sunlight
    • ISO 200 - good for outdoor photography or brightly lit indoor photography
    • ISO 400 - good for indoor photography
    • ISO 1000 or 1600 - good for indoor photography where you want to avoid using a flash
    got it?
    [/size][/font]
     
  4. vizual

    vizual → 190½ ЯBI ←

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    both descriptions have been good so far. Just figured I'd throw in some stuff in layman's terms.

    ISO will basically help you set up the situation, depending on how much light you have available while you are shooting (lower ISO for bright/outdoors, higher for lwo light). Shutter speed can manipulate the picture even further. With shutter speed you can have it fast enough to stop moving water, or slow enough to make that water look very soft and flowing.

    :dunno: if that makes sense, but it's a quickie :o
     
  5. Gutshot

    Gutshot New Member

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    iso on a digital camera is the sensititivity of the sensor to light, the higher the iso the more sensitive to light it will be, just like film.

    Your also forgetting a major part to photography which is aperture. All three play a part in your exposure.
     

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