American Society for Nondestructive Testing (ASNT) Radiographic Testing Practice Test

In radiographic testing, the size of the radiation source plays a crucial role in determining the clarity and resolution of the resulting images. A large source size can lead to increased geometric unsharpness, which can blur the image and obscure important details.

Compensating for a large source size is most effectively achieved by increasing the distance between the source and the specimen being examined. This method works because an increased source-to-specimen distance reduces the spread of radiation rays, leading to a smaller area of exposure at the detector or film. The result is a more defined image with improved detail and less distortion from the source size.

By minimizing the amount of blurring caused by the geometric spread of the source, radiographic testing becomes more accurate, allowing for better identification of defects or features within the material being inspected. This technique is a common practice in radiographic testing to ensure that the quality of the images meets the necessary inspection criteria.