The paper presents the application of the Aramis optical system for determining the bending and torsional rigidity of cold-formed C profiles. Cold-formed thin-walled beams have many advantages that are technically important. The subject of the experimental research were thin-walled cold-formed beams loaded with a concentrated force in 1/3 of the beam span. The paper presents an example of using this system as an auxiliary tool for testing the free torsion of unstiffened and stiffened C-elements. The presented results are part of the research on the impact and effectiveness of the use of longitudinal bracing made in 3D printing technology.