Bushong Chapter 16. Questions and Answers 2026

Bushong Chapter 16

Spatial resolution improves as: - answer Screen blur decreases, motion blur decreases
and geometric blur decreases

What is radiographic noise? - answer Random fluctuation in optical density of the image

What reduces quantum mottle? - answer Use of high mAs, low kVp and slower image
receptors

Radiographic quality rules: - answer1. Fast image receptors have high noise and low
spatial resolution and contrast resolution
2. High spatial resolution and contrast resolution require low noise and slow image
receptors
3. Low noise accompanies slow image receptors with high spatial resolution and
contrast resolution

What is quantum mottle? - answerrandom nature by which x-rays interact with image
receptor

Increase in Log Relative Exposure (LRE) of 0.3 results from: - answerdoubling the
radiation exposure

Optical density = - answerlog10 (Io/It)

What does higher fog density do to contrast of radiographic image? - answerReduces it

Base plus fog OD has a range of: - answer0.1-0.3

What does the reciprocity law state? - answerOD on a radiograph is proportional only to
the total energy imparted to the radiographic film

What is film contrast related to? - answerSlope of the straight-line portion of the
characteristic curve

Average gradient = - answerOD2-OD1 / LRE2-LRE1

Speed = - answer1 / exposure in roentgens to produce an OD of 1.0 plus base + fog

New image receptor speed / old image receptor speed = - answerold mAs / new mAs

How are latitude and contrast related? - answerInversely proportional