Digital Radiographic Technique and Image Quality

Spatial Resolution

The ability of an imaging system to resolve and render on the image a small high-contrast object.

Spatial Frequency

Indicates the size of objects in an image; larger spatial frequency means smaller objects.

Modulation Transfer Function (MTF)

A measure of how well an imaging system reproduces fine details of an object.

Contrast Resolution

The ability to distinguish many shades of gray from black to white.

Dynamic Range

The number of gray shades that an imaging system can reproduce.

Signal-to-Noise Ratio (SNR)

Describes how clearly the useful image information stands out from random background noise.

Dose Creep

A gradual increase in exposure over time due to digital systems hiding overexposure.

Collimation

Limits the x-ray beam to the area of interest and reduces scatter radiation.

Automatic Exposure Control (AEC