The film contrast is the ability of a film to translate contrast of various tissues to differences in the resulting image. Film contrast depends on both film characteristics and processing.

The darkroom fog is an additional optical density on a film due to light leaks or safe lights in a darkroom. Darkroom fog degrades the film contrast and must be eliminated to ensure image quality.

(CR) Computed radiography is an imaging technique that uses similar equipment to conventional radiography except that films are replaced by imaging plates. An imaging plate contains photostimulable storage phosphors, which store the radiation level received at each point in local electron energies. The imaging plate is placed under the patient in the same way as conventional film cassettes. After x-ray exposure, the imaging plate is run through a special scanner to read out the image. The digital image can then be processed to optimize contrast, brightness, and zoom. Computed Radiography can be seen as halfway between film-based conventional technology and current direct digital radiography.

(DR) Digital radiography uses a special electronic x-ray detector, which converts the radiographic image into a digital picture for review on a computer monitor. The digital image is then stored and can be post processed by changing the magnification, orientation, brightness, and contrast. Digital radiography (also called direct radiography) is a progressive development of computed radiography (CR).
These advantages can lead to fewer 'recalls' (repeated x-ray images) including a lower radiation dose than analog or conventional radiography. DR and CR systems use no chemicals to process the x-ray images and the hazardous materials and waste associated with film development are eliminated.

Advantages of digital radiography compared with conventional radiography:

A mammogram is a low dose x-ray of the breast used to detect and diagnose breast disease, or to provide a baseline reference for later comparison. Multiple images are obtained by different positioning of the breast. The breast compression during mammography is an essential component to produce an optimal diagnostic mammogram. Film mammography units use film to both capture and display the image; digital mammography units use electronic equipment.
A spot compression reduces the thickness of the area of interest and improves contrast and separation of breast tissues.