FIELD : medicine.SUBSTANCE : group of inventions relates to medicine, specifically to obtaining vital sign information of a living being. Device is configured to implement a method, comprising : illuminating at least a region of interest of a living being with light, receiving light in at least one wavelength interval reflected from at least said region of interest, generating an input signal from the received light, processing the input signal and deriving vital sign information of said living being from said input signal by use of remote photoplethysmography and controlling said illumination unit based on said input signal and/or said derived vital sign information, to enable determination of the amount of specular reflection in the area of interest and controlling said illumination unit based on the determined amount of specular reflection in order to reduce or minimise the amount of specular reflection.EFFECT : group of inventions provides improved accuracy and reliability of obtaining vital sign information of the body.10 cl, 12 dwg