An X-ray film blackens in proportion to the amount of radiation that gets through the object and hits the film. If more radiation is absorbed by the object, the object appears to be whiter (or more radiopaque) and less black (which is either known as less transradiant or less radiolucent).
The denser and more voluminous the object is, the more radiation is absorbed. If more radiation is absorbed, the object which appears on the X-ray is whiter or more radiopaque. The objects that appear to be more radiopaque on an X-ray are the tissues of the human body, such as fat and muscles.
Metal is the most radiopaque, and therefore appears to be the whitest on an X-ray. On the other hand, air or gas appears to be the blackest or the most transradiant or the most radiolucent on an X-ray. The lungs of the human body have air density, and as they are not radiopaque by themselves, they appear to be irregular and black on an X-ray.
The denser and more voluminous the object is, the more radiation is absorbed. If more radiation is absorbed, the object which appears on the X-ray is whiter or more radiopaque. The objects that appear to be more radiopaque on an X-ray are the tissues of the human body, such as fat and muscles.
Metal is the most radiopaque, and therefore appears to be the whitest on an X-ray. On the other hand, air or gas appears to be the blackest or the most transradiant or the most radiolucent on an X-ray. The lungs of the human body have air density, and as they are not radiopaque by themselves, they appear to be irregular and black on an X-ray.