Densitometer vs. Gravitometer — What's the Difference?

A densitometer is a device that measures the degree of darkness (the optical density) of a photographic or semitransparent material or of a reflecting surface. The densitometer is basically a light source aimed at a photoelectric cell.

Gravimeter

An apparatus for measuring the optical density of a material, such as a photographic negative.

Hydrometer

See densimeter.

Densitometer

A device that measures the optical density of a material.

A device that measures the specific gravity of a substance; a densimeter.

An instrument for determining optical or photographic density. A variety capable of measuring optical density of a sample at a number of different wavelengths, is called a spectrophotometer.

Same as densimeter.

A measuring instrument for determining optical or photographic density

A measuring instrument for determining density or specific gravity