One of its main advantages is its ease of operation and its safe handling because of ergonomic and compact design. Luminous source is LEDs with high long-run consistency and monochromatic light spending at low power input.
The measuring principle is the photometric method, e.g. the DPD method using reagants according to the German standard DIN 38 408. The big advantage of Photometers against comparators is that the light conditions to measure the sample are invariable, this provides higher accuracy and minimizing the chance of subjective errors.