Term
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Definition
| produce long range of grays |
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Term
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Definition
| study of film emulsions response to exposure |
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Term
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Definition
| beyond Dmax; image reversal |
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Term
reading a sensitomety curve:
steep slope indicates
- affect on exposure factor |
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Definition
fast film response, with little latitude, and higher contrast - decrease exposure
*curve is on the left |
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Term
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Definition
| leeway or margin of error one has with a given group of exposure factors - determined by kV (decreasing makes more of an effect) |
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Term
Slow II screen speed
-affect and use |
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Definition
-200
-give better detail
-good for extremities
-increase recorded detail
- increase dose |
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Term
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Definition
400
- used for thinker, denser structures, children
-lower exposure factors |
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Term
II screens
- contrast and density affect |
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Definition
-directly related to density
- no affect on contrast |
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Term
Grid ratio
-contrast and density |
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Definition
-inversely related to density
-directly related to contrast |
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Term
| minimum response/reaction time |
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Definition
| length of shortest exposure possible with a particular AEC |
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Term
AEC
error: terminating exposure too soon
-cause |
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Definition
-tissue of less density than the one of interest is center over sensor or photocell
-sensor is not completely covered
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Term
AEC
exposure terminates to late causing overexposure
- cause |
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Definition
| tissue of greater density is centered over photocell/chamber |
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Term
AEC
adjusting exposure factor |
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Definition
mAs can be adjusted by using master density control :plus/minus density, body habitus control, or measuring
- if overexposed because of an exposure shorter then minimum reaction time use lower mA station |
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