Digital Image Correlation systems are increasingly being used for non-contact measurement of deformation and strain in sheet metal components. However, the accuracy of such measurements can be significantly affected by various external and system-related factors. If these are not properly considered, substantial errors may be introduced. In this study, a short and longer flat sheet specimen were clamped in a vise to investigate how overhang and clamping stability influence the accuracy of the measured deformation fields. Two different measurement volumes were also evaluated to assess their effect on the results. These factors were evaluated through targeted experiments, and the resulting data were analyzed and interpreted. Based on the findings, recommendations were formulated to enhance the reliability of Digital Image Correlation measurements in both laboratory and industrial environments.