CAMRT Radiography Practice Exam

What is the term for an insufficient quantity of photons hitting the intensifying screen due to low exposure factors?

1. Quantum mottle

2. Film fogging

3. Image blur

4. Overexposure

The correct answer is: Quantum mottle

The term for an insufficient quantity of photons hitting the intensifying screen due to low exposure factors is "quantum mottle." This phenomenon occurs when there are not enough photons to produce a uniform exposure on the film or digital receptor. As a result, the image may exhibit a grainy appearance, which is particularly noticeable in low exposure scenarios. Quantum mottle impacts image quality by creating random variations in pixel brightness, making it difficult to discern fine details. It is directly related to the amount of radiation received and highlights the importance of selecting appropriate exposure factors to ensure sufficient photon interaction with the imaging receptor. In contrast, film fogging refers to an overall haze on the film, typically caused by exposure to light or radiation prior to actual imaging, while image blur results from motion or improper focusing during image capture. Overexposure, on the other hand, pertains to an excessive quantity of photons hitting the receptor, leading to loss of detail in the brightest areas of the image. Thus, quantum mottle is the term that accurately describes insufficient photon exposure effects on image quality.