LINEARITY of a DENSITOMETER
Purpose of the test
This test is performed to determine the linearityof a (spectro)densitometer by optical density, using a (spectro)densitometer, of a printed bar on paper.
Procedure
Operate the instrument in accordance with ISO 5-4 and the manufacturer’s instructions.
Leave the samples exposed for 24 h to 23°C and 50% R.H., according to ISO 187.
Adjust the (spectro)densitometer to the following settings: A-illuminant, Status E, polarizing.
Place the test piece in the position indicated on the cover sheet on a black backing.
Without touching the test area use the procedure appropriate to the instrument to obtain the optical densities.
Report 2 measures of optical density per level, their mean and standard deviation calculated to 3 significant figures.
ISO 5-4
Nr. of samples
A pack made of a coloured cover and 2 printed papers
Each printed paper contains 2 strips with colour bars
No special size
Levels
Level 1: White
Level 2: Black 40%
Level 3: Black 80%
Level 4: Black 100%
Density:
Level 1: -0.01÷0.03
Level 2: 0.3÷0.4
Level 3: 0.5÷1.5
Level 4: 1.0÷2.5
Reporting
Report 2 measures of Optical Density per field, their mean and their standard deviation. All to three significant digits.