The ID measures small parts

The ID uses a glass target graticule with small sub-measurement zones. The transmission of a single 4x4mm square can be measured- ID can be assessed on a single area of 6x2mm. Traditional Haze and Clarity meters can only measure parts bigger than 20mmx20mm and have an open port into the instrument.

The Rhopoint ID is more suited to small parts than a traditional instrument.