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Thread: Apertures of digital cameras

  1. #1

    Question Apertures of digital cameras

    Can anyone explain to me how to convert apertures of digital cameras to their equivalent in 35mm SLRs?
    I'm using a canon g2, and the aperture ranges from 2.1 to 8.0, so... like what's the equivalent of a f/16 for example?

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    The f-stop does not need conversion. It is related to the amount of light that passes through the lens.

    Are you talking about the equivalent depth of field between 35 mm and digital cameras?

  3. #3

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    Yeah, something like DoF.
    What i mean is, how do i know what aperture to use for example on a sunny day (for SLR, there's the sunny f/16 rule, but what's the equivalent for a canon g2??)

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    Originally posted by kree
    Yeah, something like DoF.
    What i mean is, how do i know what aperture to use for example on a sunny day (for SLR, there's the sunny f/16 rule, but what's the equivalent for a canon g2??)
    The exposure rules will still apply as they are all based on film speed eqivalence, so for example the sunny f16 rule still applies to digital. Just be aware that digital has a greater dynamic range than film so you may need to tweek the values somewhat to suit your camera.
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  5. #5

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    err how do i use the sunny f/16 rule when the minimum aperture is 8.0???

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    Originally posted by Ian
    Just be aware that digital has a greater dynamic range than film so you may need to tweek the values somewhat to suit your camera.
    I thought film has a greater dynamic range than digital.

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    Originally posted by linse
    I thought film has a greater dynamic range than digital.
    Typical dynamic ranges (in stops)

    Slides (Chromes) 5-6 stops
    Colour Negs: 7-8 stops
    B/W film 7-9 stops
    Digital Sensor 8-12 stops.
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    Originally posted by kree
    err how do i use the sunny f/16 rule when the minimum aperture is 8.0???
    Stop down to f16 is how
    The Ang Moh from Hell
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  9. #9

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    correct me if im wrong, but if the minimum aperture is 8.0 (or f/8.0), then how do i stop down further (eg to f/16)?

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    Originally posted by Ian
    Typical dynamic ranges (in stops)

    Slides (Chromes) 5-6 stops
    Colour Negs: 7-8 stops
    B/W film 7-9 stops
    Digital Sensor 8-12 stops.
    Well, you're right about digital sensors having greater dynamic range but unfortunately my brief research indicates it's mainly in the shadows. I believe there's less dynamic range in the highlights. That's why I find it easier to blow out highlights in digital shots compared to film.

    Originally posted by kree
    correct me if im wrong, but if the minimum aperture is 8.0 (or f/8.0), then how do i stop down further (eg to f/16)?
    Basically, you can't. It's a physical limitation of your camera. Anyway, why do you want to use F16 anyway. Can't you just increase the shutter speed? If you want more depth of field, the F8 aperture in your camera is probably greater than equivalent F22 with 35 mm film anyway.

  11. #11

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    Originally posted by linse
    Well, you're right about digital sensors having greater dynamic range but unfortunately my brief research indicates it's mainly in the shadows. I believe there's less dynamic range in the highlights. That's why I find it easier to blow out highlights in digital shots compared to film.
    I think that dynamic range refers to the entire range between the brightest/highest representable value and the lowest/darkest one. Hence, when one refers to dynamic range, it is a single value, i.e a range.

    What you seem to be referring to above is exposure latitude, i.e tolerance to over/underexposure given a set exposure value.

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    Originally posted by Zerstorer
    I think that dynamic range refers to the entire range between the brightest/highest representable value and the lowest/darkest one. Hence, when one refers to dynamic range, it is a single value, i.e a range.

    What you seem to be referring to above is exposure latitude, i.e tolerance to over/underexposure given a set exposure value.
    Yeah, but isn't exposure latitude directly related to the dynamic range?

  13. #13

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    Originally posted by linse
    Yeah, but isn't exposure latitude directly related to the dynamic range?
    Yes, but dynamic range is the whole range, from brightest representable value to the darkest.

    Exposure latitude is how many stops above and below the given exposure, before the range is exceeded.

    Think of exposure latitude as how the entire usable dynamic range is divided. (an arbitrary example would be when exposures are at the 70% mark, where it has only 30% more before the highlights are blown but 70% below before nothing is registered)

    Well, at least this is my understanding of it.

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