Sometimes, an x-ray machine will be used that resembles a large table. In this case, the patient will lie down on the flat surface with the recording plate lowered onto his or her chest and with the x-ray tube suspended approximately 40 inches above the patient (see illustration at left).

When the radiologist is ready to activate the procedure, the patient is asked to remain still and take a deep breath and hold it. The procedure is quick and straightforward. More than one view may be taken, including a posterior to anterior view, with the patient's front against the recording surface, and a side, or lateral, view, with the patient's left side against the recording surface. A small dose of radiation enters the chest and a "picture" is taken of its internal structure, recorded either on film or on a digital plate.

The more radiation that is absorbed, the lighter in tone an anatomical structure will appear to be on the x-ray image. For example, lung tissue absorbs very little radiation and will appear dark gray while bones, which absorb more of the x-rays, will appear white or light gray.

The radiologist will inspect the images and report their interpretation to the patient's primary care physician or other health care provider, who will then report the findings to the patient or patient's family.