Final answer:
Radiographic contrast is mainly affected by kV due to its effect on X-ray energy and tissue penetration, application of processing algorithms that manipulate the image data, and the signal to noise ratio, which indicates the clarity of useful image information over background noise.
Step-by-step explanation:
Radiographic contrast in a digital image is primarily affected by a variety of factors. One such factor is kV (kilovoltage), which influences the energy of the X-rays used in imaging and, in turn, affects the contrast of the radiograph. The higher the kV, the more energy the X-rays have, resulting in more penetration through tissues and thus a lower image contrast, as differences between tissues are less distinguishable.
Application of processing algorithms also significantly influences radiographic contrast. These algorithms can enhance or diminish contrast through the manipulation of image data, affecting the visibility of details within the image. Lastly, Signal to noise ratio (SNR) is crucial as it describes the amount of useful information (signal) in comparison to the background noise. A higher SNR typically indicates a clearer image with better contrast. Though not primarily affecting contrast, matrix size relates to image resolution, which determines the sharpness and detail of the image.