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Miles Rhodes,
Wine Taster
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IRIS DIAPHRAGM: By adjusting the size of the aperture in the iris one can control the depth of field and achieve certain sharpness effects on the sights.
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Richard Hosking,
Paranormal Investigator
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Thus a 28mm wide angle lens set at f11 produces greater depth of field than a normal lens set at the same aperture and the normal lens produce greater depth of field than a 200mm lens.
Another feature is the lack of depth of field produced by lens photography, all objects appear equally sharp from the nearest point to infinity.
There are three main factors that control the how much depth of field your lens produces in a given situation, these are the aperture setting on the lens, your distance from the subject and the focal length of the lens you are using.
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Adam Findley,
Professional Motivator
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But with the depth of field control of your lens you can over come these difficulties, by choosing a shallow depth of field, the resulting picture should result in only your friend appearing in focus with the unattractive background no more than an indistinct blur.
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Rob Verdann,
Afterdark Removalist
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I read that it all depends on aperture but it really seems to depend on the length of the lens, with a long lens there is much less depth of field than with a short lens and with a zoom lens there is less at 200mm than at 70mm.
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Dave Simons,
Internet Entrepeneur
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If you think about it, if your lens' widest aperture provides the least depth of field and its narrowest aperture provides the most depth of field, then the aperture settings in between the widest and narrowest must provide varying degrees of depth of field.
The Aperture Priority Exposure mode allows the photographer to choose apertures to control depth of field, while the camera automatically selects the correct shutter speed using TTL metering.
Then the CPU calculates the necessary aperture value to produce depth of field which will cover both points at a 0.
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Arthur Dawkins,
Astro-physicist
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The dSam Depth of Field Charts , manufactured by OpTex is a method of exploring and then assessing the depth of field of a particular lens set at a particular aperture photographically by using a three dimensional test chart based on a systematic optical mathematical range of test chart distances and spatial frequency targets on each chart.
The aperture is set for f11, so using the depth of field scale as explained earlier, we know that distances between the two f11 engravings on the depth of field scale will appear in focus in the final photograph.
DEPTH OF FIELD WITH INFINITY FOCUS One approach to depth of field is to focus on infinity and set a small enough lens aperture so everything important in your photograph will be resolved.
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