The main task of the research is to compute precise gravity field and quasi-geoid model up to 1 cm accuracy using all available data. In the year of 2016 quasi-geoid model for Eastern part of Latvia has been computed using Karlsruhe University of Applied Sciences developed DFHRS (Digital finite-Element Height Reference Surface) software v.4.2., which allowed the combination of GNSS/levelling data together with global geopotential models e.g. EGM2008. But some inconsistencies were found by comparing the use of different geopotential models as input data and now new kind of observations provided by Digital Zenith Camera - deflections of vertical - are used in order to check these inconsistencies and improve qgeoid model.