Radiography II - Imaging Factors

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Besides safety, the ultimate goal of the RT technician is to produce the highest quality radiographic image possible in order to assess the fitness of service of the specimen being tested.

Understanding radiographic sensitivity and the characteristics and variables of radiation and film - such as density, contrast, sharpness, magnification, and distortion, and what affects contrast and what affects definition - will help make that possible.

For example, overexposure of a radiography will produce darker images, or higher densities. Likewise, material thickness also affects contrast as radiation exposure is greater upon thinner sections than thicker ones. Figuring out the balance between all these factors will help you produce the greatest radiographic sensitivity, further ensuring your images show the highest amount of detail (and are therefore the most comprehensive image) possible.

NDT Classroom’s online courses in Radiographic Testing offer an in-depth look at the factors that affect the quality of a radiographic image and how to interpret what an image is showing. With high-def, real-world video examples, the courses clearly demonstrate how you as a technician can handle and maneuver variables to get the best image possible, providing you with the means to create better images. And better images = better understanding of any issues, which then = better chances to get at the root of the problem and fix it. And that is, ultimately, the end goal – accurately assessing and fixing the problem in order to create a safer world for all.  

Want to learn more about imaging factors and radiographic testing? Click here for an overview of NDT Classroom's Level I and Level II courses.

A Look at Radiographic Testing


Radiographic testing is an excellent NDT method to learn, as it offers many advantages over other NDT methods for specific applications.

For one, it can be used on a variety of materials and requires very little surface prep. It is also highly reproducible and often uses portable systems, making it easy to use in elevated positions and in the field.

However, it does not come without its drawbacks, such as the potential for health risks if tests are not performed with the utmost care. But administering tests well and being able to produce a high-quality radiograph is only half the battle. RT Technicians also need to be skilled in interpreting and evaluating the results of the tests they perform. To do so, they must be able to rely on their visual acuity and understand the roles that effects and scattering play in film interpretation.

There are three basic steps involved in interpreting radiographs:

1. Detection

2. Interpretation

3. Evaluation

If there are discontinuities present in the test material, they will affect the amount of radiation that passes through. For example, x-rays or gamma rays will pass through porosity with relative ease as compared to the other solid parts of the same material. This will create a higher exposure and result in a darker region of the finished radiograph. This specific, hands-on knowledge is the kind of information you can expect from the Radiographic Testing courses offered by NDT Classroom.

Led by industry expert Gary Larson, NDT Classroom’s Radiographic Testing Levels I and II courses take you through all the knowledge and steps necessary to lay the foundation for becoming a highly skilled radiographic technician. Not only do they provide the know-how, though; they give you the confidence you need to do the job with the highest level of safety.

Find out more about our RT courses here