FILM FACTORS

Question 1

• The study of the relationship between the intensity of exposure of the
film and the blackness after processing is called

Answer 1

sensitometry

Question 2

6 types of FILM FACTORS

Answer 2

SPEED, PROCESSING TIME, PROCESSING TEMPERATURE, LATITUDE, DENSITY, CONTRAST

Question 3

The two principal measurements involved in sensitometry are the
____ and ______
the processed film.

Answer 3

exposure to the film and the percentage of light transmitted through

Question 4

The two principal measurements involved in sensitometry are the
____ and ______
the processed film.

Answer 4

exposure to the film and the percentage of light transmitted through

Question 5

It describe the relationship between OD and radiation exposure.

Answer 5

H & D curve
Hurter and Driffield

Question 6

– low radiation exposure level

Answer 6

Toe

Question 7

– intermediate radiation exposure level
– the region in which a properly exposed
radiograph appears

Answer 7

Straight line portion

Question 8

– high radiation exposure level

Answer 8

Shoulder

Question 9

Apparatus that are needed to construct a characteristic curve:

Answer 9

1. Optical step wedge / sensitometer
2. Densitometer - a device that measures OD

Question 10

Apparatus that are needed to construct a characteristic curve:

Answer 10

1. Optical step wedge / sensitometer
2. Densitometer - a device that measures OD

Question 11

The degree of blackening on the radiograph.
• It is a logarithmic function.
• Has a precise numeric value that can be calculated if the level of
light incident on a processed film (Io) and the level of light
transmitted through that film (It
) are measured.

Answer 11

OPTICAL DENSITY

Question 12

is attributable to the composition of the base and the tint
added to the base to make the radiograph more pleasing to the eye.

Answer 12

Base density

Question 13

Base density has a value of approximately .

Answer 13

0.1

Question 14

results from inadvertent exposure of film during storage,
undesirable chemical contamination, improper processing, and a
number of other influences.

Answer 14

Fog density

Question 15

Fog density on a processed radiograph should not exceed .

Answer 15

0.1

Question 16

The useful range of OD is approximately

Answer 16

0.25 to 2.5.

Question 17

Base plus fog OD has a range of approximately

Answer 17

0.1 to 0.3.

Question 18

The ____ states that the OD on a radiograph is proportional
only to the total energy imparted to the radiographic film and
independent of the time of exposure.

Answer 18

reciprocity law

Question 19

Whether a radiograph is made with short exposure time or long
exposure time, the reciprocity law states that the

Answer 19

OD will be the same
if the mAs value is constant.

Question 20

The difference in optical density.

Answer 20

High Contrast
Low Contrast

Question 21

• radiograph that has marked differences in OD

Answer 21

high contrast

Question 22

• the OD differences are small and are not distinct

Answer 22

low contrast

Question 23

is the product of image receptor contrast and
subject contrast.

Answer 23

Radiographic contrast

Question 24

is inherent in the screen-film combination and
is influenced somewhat by processing of the film.

Answer 24

Image receptor contrast

Question 25

is determined by the size, shape, and x-ray attenuating characteristics of the anatomy that is being examined and the energy (kVp) of the x-ray beam.

Answer 25

Subject contrast

Question 26

The average gradient is the slope of a straight line drawn between two points on the characteristic curve at ODs __ and __ above base and fog densities. This is the approximate useful range of OD on most radiographs.

Answer 26

0.25 and 2.0

Question 27

Most radiographic image receptors have an average gradient in the range of

Answer 27

2.5 to 3.5.

Question 28

is probably more important than average gradient for general radiography because many clinical ODs appear in the toe region of the characteristic curve.

Answer 28

Toe gradient

Question 29

is more important for mammography.

Answer 29

Midgradient or shoulder gradient

Question 30

• Fast/high speed IR • Par speed • Slow/low/detail IR • Slow speed → less noise → more patient dose • Fast speed → more noise → less patient dose

Answer 30

- more than 100 - 100 - less than 100

Question 31

→ long gray scale → low contrast

Answer 31

Wide latitude

Question 32

→ short gray scale → high contrast

Answer 32

Narrow latitude

Question 33

is required for optimal image receptor contrast because the degree of development has a pronounced effect on the level of fog density and on the ODs resulting from a given exposure at a given image receptor speed.

Answer 33

Proper film processing

Question 34

FACTORS THAT MAY AFFECT THE FINISHED RADIOGRAPH

Answer 34

-CONCENTRATION OF PROCESSING CHEMICALS -DEGREE OF CHEMISTRY AGITATION DURING DEVELOPMENT -DEVELOPMENT TIME -DEVELOPMENT TEMPERATURE