The linearity of the response is measured using strips of neutral density filter, the graph of absorbance against the number of strips should be a straight line.

The results shown are highly linear from 0-2 absorbance units (i.e. 100% - 1% transmittance). Above 2 the linearity is less precise but there are few applications for which this region of the graph would be used - above 2A less than 1% of the available light is passing through the sample.

In stand alone mode the maximunm absorbance that can be displayed is 1.999A and the minimum transmittance 0.1%.

Readings are shown to three decimals (absorbance) or 1 decimal (transmittance).