Optical measuring systems based on digital image correlation method (DIC) becoming increasingly popular over last few years by substituting the conventional data acquisition systems implemented during the physical tests of different materials and structures. In current research the gom/ARAMIS 3D strain measuring system has been utilised to acquire full strain and displacements map over the specimen surface for small scale sandwich specimens with DendroLight® core. A 4-point bending setup has been used to demonstrate that ARAMIS could deliver much more detailed in-plane and out-of-plane strain data compared to conventional strain-gauges. Developed strain patterns on the specimen surfaces acquired with DIC have been compared with finite element model by ANSYS computer code with shell type finite elements. A general good agreement has between achieved among numerical and experimental results in small deflection region - below 1/250 of span length.