newbie's question on ISO and Depth of Field

Discussion in 'Digital Photography' started by Hoover, Apr 9, 2006.

  1. Hoover

    Hoover Guest

    If you want to highlight images in the foreground and blur the background,
    should the F stop numbers be small or large?
    Regarding ISO, in general should ISO be set at 200 for inside photos and
    higher ISO's for outside?
     
    Hoover, Apr 9, 2006
    #1
    1. Advertising

  2. Hoover

    Jim Guest

    "Hoover" <> wrote in message
    news:J4ZZf.4001$s%6.408@dukeread02...
    > If you want to highlight images in the foreground and blur the background,
    > should the F stop numbers be small or large?

    Small
    > Regarding ISO, in general should ISO be set at 200 for inside photos and
    > higher ISO's for outside?

    No
    Jim
    >
    >
     
    Jim, Apr 9, 2006
    #2
    1. Advertising

  3. Hoover

    Yomama Guest

    Big help

    "Jim" <> wrote in message
    news:B8ZZf.575$...
    >
    > "Hoover" <> wrote in message
    > news:J4ZZf.4001$s%6.408@dukeread02...
    >> If you want to highlight images in the foreground and blur the
    >> background, should the F stop numbers be small or large?

    > Small
    >> Regarding ISO, in general should ISO be set at 200 for inside photos and
    >> higher ISO's for outside?

    > No
    > Jim
    >>
    >>

    >
    >
     
    Yomama, Apr 9, 2006
    #3
  4. Hoover

    Mobius Guest

    "Hoover" <> wrote in message
    news:J4ZZf.4001$s%6.408@dukeread02...
    > If you want to highlight images in the foreground and blur the background,
    > should the F stop numbers be small or large?
    > Regarding ISO, in general should ISO be set at 200 for inside photos and
    > higher ISO's for outside?

    I'm somewhat new to many of the terms though I've had some experience so I
    can try to answer some of the questions (anyone else please correct me if
    I'm wrong here, most of all when to use ISO settings).

    The ISO is the film exposer I believe, I know it does effect the amount of
    light picked up.

    BACKWARDS is actually reverse (think more like golf compared to other
    sports, higher number is less).

    100 is more outdoor, 200 indoor or outdoor lower lighting, 400 is outdoor at
    sunset & low lighting & indoor with low lighting, 800 is for even darker,
    1600 is more for night/very dark.

    I do know the F-stop arpature setting is also similar. The larger the # the
    less light gets into the lense because its the size of the lense when open,
    but as the lower number in the fraction (1/f) for the radious.

    Fx = 1/x radious = 1/(x^2 or x * x) total light
    (just memorize the square roots of numbers which are exponential increases
    for 2)

    F1.4 (1.41421356...) 1/1.4 radious = 1/2 total light
    F2 = 1/2 radious = 1/4 total light
    F2.8 = 1/2.8 (2.828427....rounded) radious = 1/8 total light
    F4 = 1/4 radious = 1/16 total light
    F5.6 (5.656854....) = 1/5.6 radious = 1/32 total light
    F8 = 1/8 radious = 1/64 total light
    F11 (11.313708...) = 1/11 radious = 1/128 total light
    F16 = 1/16 radious = 1/256 total light
    F22 (22.62741699796952...) = 1/22 radious = 1/512 total light
    F32 = 1/32 radious = 1/1024 total light

    Thats the way I read & understood it.
     
    Mobius, Apr 9, 2006
    #4
  5. "Hoover" <> writes:
    > If you want to highlight images in the foreground and blur the
    > background, should the F stop numbers be small or large?


    Small. The f-stop number is really expressed as a ratio. That is why
    we write it like this: "f/2" - where "f" is the focal length of the
    lens. f/2 says that the aperture diameter is half of the focal length
    of a lens. So if we are talking about a 50 mm lens f/2 means that the
    aperture is 25 mm wide, while f/11 means that it is 4.55 mm wide.

    A wider aperture means a more shallow depth of field, so for a
    shallow depth of field, you use a small f-stop.

    > Regarding ISO, in general should ISO be set at 200 for inside photos
    > and higher ISO's for outside?


    Asssuming there is less light inside than outside, you do it the
    opposite. High ISO for low light/inside, low ISO for much light/
    outside.
    --
    - gisle hannemyr [ gisle{at}hannemyr.no - http://hannemyr.com/photo/ ]
    ------------------------------------------------------------------------
    Sigma SD10, Kodak DCS460, Canon Powershot G5, Olympus 2020Z
    ------------------------------------------------------------------------
     
    Gisle Hannemyr, Apr 9, 2006
    #5
  6. Hoover

    kctan Guest

    There are 3 factors actually for question 1.
    1. Small f/number = large aperture
    2. Use longer focal length lens, the longest the better
    3. Stand close to the subject, as close as possible yet maintain your
    required cropping.

    They interact so visually do it by taking the 3 factors into consideration.

    There is no specific ISO for question 2. Any ISO can take picture both
    inside and outside.
    But generally, higher ISO is for inside photos when its available light are
    too low for lower ISO to perform. Image will be "nosier".


    "Hoover" <> wrote in message
    news:J4ZZf.4001$s%6.408@dukeread02...
    > If you want to highlight images in the foreground and blur the background,
    > should the F stop numbers be small or large?
    > Regarding ISO, in general should ISO be set at 200 for inside photos and
    > higher ISO's for outside?
    >
     
    kctan, Apr 9, 2006
    #6
  7. Hoover

    Neil Ellwood Guest

    On Sat, 08 Apr 2006 21:04:44 -0400, Hoover wrote:

    > If you want to highlight images in the foreground and blur the background,
    > should the F stop numbers be small or large?

    Small.
    > Regarding ISO, in general should ISO be set at 200 for inside photos and
    > higher ISO's for outside?

    100 for outside higher for inside - but don't overdo it.
    --
    Neil
    delete 'l' to reply
     
    Neil Ellwood, Apr 9, 2006
    #7
  8. "Hoover" <> writes:

    > If you want to highlight images in the foreground and blur the background,
    > should the F stop numbers be small or large?


    The number should be small, meaning that the actual aperture in the
    lens is large. You're going for shallow dept of field.

    > Regarding ISO, in general should ISO be set at 200 for inside photos and
    > higher ISO's for outside?


    No, the reverse; higher ISO numbers inside (where there's less light
    in general), lower ISO numbers outside (where it's brighter in
    general).
    --
    David Dyer-Bennet, <mailto:>, <http://www.dd-b.net/dd-b/>
    RKBA: <http://www.dd-b.net/carry/>
    Pics: <http://dd-b.lighthunters.net/> <http://www.dd-b.net/dd-b/SnapshotAlbum/>
    Dragaera/Steven Brust: <http://dragaera.info/>
     
    David Dyer-Bennet, Apr 9, 2006
    #8
  9. Hoover

    m Ransley Guest

    With many digital p&s noise is an issue above 100. If I want highest
    quality I only use 100iso. Noise is dependant on your camera, most
    Panasonic are noisy above the lowest setting, most dslr have great
    flexibility from better sensors and noise may not be an issue till near
    the maximum iso. dpreview should have a noise iso comment on your
    camera or sensor.
    You dont say what camera or lens you refer to, on my p&s I cant get out
    of focus backgrounds like I can with my A1. P&S are limited in
    flexibility.
     
    m Ransley, Apr 9, 2006
    #9
  10. Hoover

    Don Stauffer Guest

    Hoover wrote:
    > If you want to highlight images in the foreground and blur the background,
    > should the F stop numbers be small or large?
    > Regarding ISO, in general should ISO be set at 200 for inside photos and
    > higher ISO's for outside?
    >
    >

    Smaller f/stop, which is of course a LARGER aperture. This is the
    confusing thing. Large apertures mean shallow depth of field, but large
    numbers mean small apertures and vis versa.

    High ISO for dim light. Low as possible if there is enough light.
    Night outdoors might require high ISO, so it is a bright light/dim light
    thing, not an indoors/outdoors.
     
    Don Stauffer, Apr 9, 2006
    #10
  11. Hoover

    Hoover Guest

    Thanks to all of you who responded - this is confusing as hell but I think i
    understand it more now -
    A hypothetical - for a landscape, in which you want to have as clear a photo
    as possible from foreground to background, I assume you use a large F# as
    possible.
    If you have, say, a deer nearby and you want to blur the wooded area behind
    it, you would use a small F#? Make sense?

    "Don Stauffer" <> wrote in message
    news:J6b_f.26$...
    > Hoover wrote:
    >> If you want to highlight images in the foreground and blur the
    >> background, should the F stop numbers be small or large?
    >> Regarding ISO, in general should ISO be set at 200 for inside photos and
    >> higher ISO's for outside?

    > Smaller f/stop, which is of course a LARGER aperture. This is the
    > confusing thing. Large apertures mean shallow depth of field, but large
    > numbers mean small apertures and vis versa.
    >
    > High ISO for dim light. Low as possible if there is enough light. Night
    > outdoors might require high ISO, so it is a bright light/dim light thing,
    > not an indoors/outdoors.
     
    Hoover, Apr 9, 2006
    #11
  12. Hoover

    miles Guest

    Hoover wrote:
    > If you want to highlight images in the foreground and blur the background,
    > should the F stop numbers be small or large?


    Smaller. A larger lens opening results in less depth of field and
    vis-versa.

    > Regarding ISO, in general should ISO be set at 200 for inside photos and
    > higher ISO's for outside?


    Depends on lighting more than being inside vs. outside. The less light
    the higher the ISO may be required. Too low of an ISO for the lighting
    conditions may result in too low of a shutter speed or you'll get into
    undesired effects of depth of field as above.

    In the days of 35mm film I generally shot at 1/60th indoors with a flash
    and 120th outdoors in the sun. That was because of low ISO films I used
    to get finer grain. Slower than 1/60th and you'll want a tri-pod
    although a camera with image stabilization seems to compensate for
    unsteady hands. F-Stop, ISO and shutter speed really depend on just
    what you're trying to achieve for a given picture.
     
    miles, Apr 9, 2006
    #12
  13. Hoover

    TMG Guest

    Hoover wrote:
    > Thanks to all of you who responded - this is confusing as hell but I think i
    > understand it more now -
    > A hypothetical - for a landscape, in which you want to have as clear a photo
    > as possible from foreground to background, I assume you use a large F# as
    > possible.


    Yes: greater depth = greater f/stop

    > If you have, say, a deer nearby and you want to blur the wooded area behind
    > it, you would use a small F#? Make sense?


    Yes: lower depth = lower f/stop.

    And for the ISO issue, it can be thought of as "sensitivity". The higher
    then number, the more sensitive the sensor. Just like in the film world.
    Higher ISO (or for us older film users, ASA) means the emulsion reacts
    faster, or to lower light.
     
    TMG, Apr 10, 2006
    #13
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. jean

    Question on depth of field

    jean, Feb 22, 2004, in forum: Digital Photography
    Replies:
    14
    Views:
    488
  2. Bryce

    D10 question - depth of field preview

    Bryce, Feb 23, 2004, in forum: Digital Photography
    Replies:
    52
    Views:
    1,396
    Bryce
    Feb 27, 2004
  3. Nick Good

    Depth of Field and HFD calculator for digital and film

    Nick Good, Aug 27, 2004, in forum: Digital Photography
    Replies:
    1
    Views:
    486
    Huygens
    Aug 27, 2004
  4. Robert11

    Depth of Field Quest. From Newbie, Please

    Robert11, Aug 29, 2004, in forum: Digital Photography
    Replies:
    19
    Views:
    389
    Alan Browne
    Aug 31, 2004
  5. Over G

    depth of field and apparture, basic question..

    Over G, Apr 12, 2007, in forum: Digital Photography
    Replies:
    7
    Views:
    782
    Don Stauffer in Minnesota
    Apr 13, 2007
Loading...

Share This Page