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18 Cards in this Set
- Front
- Back
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What are the five quality factors of an image? |
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What three things affect חדות? |
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What affects geometric חדות? |
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There is always some ____ in an x-ray. |
magnification |
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When the object is farther from the film, there is ____ magnification. When the tube is farther from the film, there is ____ magnification. |
more, less |
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Magnification = |
FFD / FFD - OFD |
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Reducing magnification improves _____. |
geometric resolution. |
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What are the two ways to improve geometric resolution? |
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What is a half shadow? |
Penumbra--the shadow surrounding an object, appears as a blurry border. |
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What is the record of the actual object called? |
Umbra |
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Half shadow - Geometric resolution ? |
Half shadow -Geometric resolution + |
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What are three ways to reduce penumbra? |
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For low magnification and small half shadow, use a ____ and a _____. |
short OFD, small focal spot |
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Distortion refers to _____. |
wrong shape, wrong size (magnification), or wrong position |
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Distortion can be caused by a tilted ____ . |
object OR film |
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True or false. Some distortion always occurs. |
True |
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We can counter distortion by _____. |
Taking two x-rays |
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Explain what geometric resolution is and how we can improve it. |
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