Ch. 26 Density/Image Receptor Exposure (Exp I) Flashcards
The density of the radiographic image in a film-based environment is the…
- Easiest prime technical factor to evaluate
- Result of black metallic silver deposited on a film
- Degree of overall blackening of the image
The optical density range visible to the human eye is:
0.25 to 2.50
The brightness of the image on a viewing monitor is:
A function of the monitor
The principal controlling factor of radiographic image density is:
mAs
Which statement is FALSE:
a. As mAs increases, exposure increases
b. As. mAs decreases, density increases
c. As mAs increases, density increases
d. As mAs decreases, exposure increases
d. As mAs decreases, exposure increases
The minimum change necessary to cause a visible shift in density is _____ percent of mAs.
25-35
Which generator produces the least amount of radiographic density per mAs?
a. Single phase, 2 pulse
b. Three phase, 6 pulse
c. Three phase, 12 pulse
d. High-frequency generator
A. Single phase, 2 pulse
Which generator produces the greatest amount of radiographic density per mAs?
a. Single phase, 2 pulse
b. Three phase, 6 pulse
c. Three phase, 12 pulse
d. High-frequency generator
d. high-frequency generator
Which rule is used as a guide to maintain the same density when kVp changes?
15% rule
Which factor influences the number of photons reaching the IR?
mAs
Which factor influences the average energy of photons reaching the IR?
kVp
The 15% rule changes:
Density and contrast
The relationship between exposure and SID is:
Inversely proportional to the square of the distance
The density maintenance formula mathematically resembles the:
Inverse square law
What conclusion can you reach regarding an image with an S# of 750 and good radiographic image density on the display monitor?
The image is likely to demonstrate noise or quantum mottle
A severely underexposed film image will:
Be unable to visualize recorded detail
In the event of making a single exposure that is critical to the exam success, most experienced technologists will:
- Overexpose the IR slightly
- Provide enough exposure to permit viewing with a bright light or adequate histogram analysis
In the case of film radiography, the response to exposure is:
Logarithmic
Image brightness on an image display monitor is controlled by:
Window level
The effect of mAs upon IR exposure is:
Directly proportional
Optimum IR exposure to an IR is:
1 mR plus or minus 33%
As you analyze your image, you come to the conclusion that is must have more exposure. As a general rule, you should increase:
mAs by 2x
A change in kVp, as an exposure factor, affects:
- The amount of scatter production
- Beam intensity
- Average beam energy
The greatest factor in the production of scatter radiation is:
Patient thickness
Radiographic room A is a three-phase, 6-pulse generator. Room B is a high frequency generator. When going between these two rooms to perform examinations, what exposure modification is necessary to produce comparable exposure density?
No change is required between the two systems
Focal spot blooming occurs with:
High mAs
Because of the “heel effect,” x-ray beam intensity:
Is greater under the cathode side of the tube
The anode heel effect is more pronounced with:
A 10 degree target angle
When changing your SID from 72” to 56”:
Decrease your mAs by 50%
All of the following will increase radiographic film density EXCEPT:
a. Increased developer temperature
b. Increased dryer temperature
c. Increased immersion time in developer
d. Increased developer concentration
b. Increased dryer temperature
