What is Densitometer used for ?
A densitometer is a piece of scientific equipment designed to measure optical density. Densitometers are used in a variety of scientific applications as well as by photographers and printers who want to control the quality of their work. Numerous companies produce densitometers, including special equipment customized for specific applications.
Some densitometers use a transmission technique where light is passed through the material being measured, and a photoelectric cell reads as the light passes. Optical density is determined by seeing how much light is transmitted through the object being read. This type of densitometer is used to measure the optical density in film, the data is used in various ways in the film development process.
A reflection process can be used with solid objects that cannot be used with a transmission densitometer. In this case, the amount of light reflected by the object is measured. For example, a photographer can use the transfer method to read film and the mirror method to read an advanced photograph. Some densitometers have both functions that allow people to adjust for a variety of uses.
Printers can use densitometers to check color saturation and confirm that a print run is consistent. The densitometer is also used during printing checks to verify that the material is properly printed and to compare the appearance of the films used to prepare the printing plates with the resulting printing product.
Densitometry is used in a variety of ways. In a special type of densitometry used to measure bone density, density is measured by passing x-rays through the body. In this case, bone density can be determined by seeing how many x-rays have passed. Extreme changes in bone density can often be identified by looking at x-ray film because more porous bone shows darker color on the x-ray, while denser bone appears whiter and has been exposed to x-rays, indicating that these areas of the film are not very dense.