RADIOGRAPHIC QUALITY TERMS Flashcards
ability to image two separate objects as being distinct
resolution
ability to distinguish anatomic structures of a similar subject contrast
contrast resolution
ability to image small objects that have high subject contrast
spatial resolution
measures film blackening
optical density
inversely proportional to optical density
light transmittance (%T)
compares exposure vs optical density
characteristic film curve
inherent property of a film, determined by the slope of the straight line portion of the characteristic curve
so increased slope = increased film contrast
film contrast
range of exposures over which the image receptor responds with ODs in a diagnostically useful range
latitude
gray scale expansion or compression; basically taking the 1000s of gray tones from the photon beam and turning into the 32 gray tones the Hyman eye can distinguish
windowing
name this variable of the windowing?
the value of each pixel is changed by addition or subtraction
window level (density)
name this variable of the windowing?
the value of each pixel is changed by addition or subtraction
window width (contrast)
name this contrast
density differences that result due to the type of film used, how it was exposed, and how it was processed
film contrast
name this radiographic contrast
image contrast that results from patient interactions
subject contrast
name this radiographic contrast
unwanted density from non-exposed silver halide grains being developed
film fog
is film fog or scatter radiation
unwanted density from non-exposed silver halide grains being developed
film fog
