lesson 2 Flashcards
blackening of the finished radiograph
density
light and dark areas on the image
contrast
degree of appearance of the edge between two density areas in the imaging subject
detail/sharpness
larger than the object they represent
magnification
unequal magnification of different portions of the same object
distortion
blurring of the image
motion
distance between source and image receptor
source to image distance
distance between object and image receptor
object to image distance
a phosphor material which converts x-ray energy into light photons
Intensifying screen
device which measures density of the xray film
densitometer
mAs (milliampere-second)
- primary controls the quantity of the xray
- directly affects the density
kVp (kilovoltage-peak)
- controls the quality of the x-ray beam
- affects radiograph contrast
- responsible for penetration
- secondary of scatter radiation
types of contrast
- high contrast
- low contrast
great difference between transmitted densities
high contrast
less or slight difference between the transmitted densities
low contrast
ability to image two separate object of very similar subject contrast
resolution
types of resolution
- low contrast resolution
- high contrast resolution
involves object of very similar subject contrast
low contrast resolution
refers to object having high subject contrast
high contrast resolution
factors affecting geometric detail
- motion
- focal spot size
- OID
- SID
- IS speed
- film-screen contact
- non-screen holder
- target object film alignment
movements of the parts of the body that can be controlled
voluntary motion
movements of the body parts that cannot be controlled
involuntary motion
time to beat the motion of the heart
0.05 sec
penumbra effect is caused by what
- large effective focal spot
- short SID
- long OID
