Determination of the SMC MF. Panel a: m_F322W2 vs. m_F115W − m_F322W2 CMD for stars in the SMC. The magnitude intervals are highlighted in different colors, with the corresponding average stellar masses labeled on the right. The red solid line shows the isochrone that best fits the observed stellar population. Panel b: zoom-in of the CMD focusing on the magnitude range 21.0 < m_F322W2 < 24.3. Colored regions indicate the bins used to compute the MF along the upper MS, tailored to include binary stars. Panels c and d: m_F322W2 luminosity function (panel c) and corresponding MF (panel d) for SMC field stars. White points mark bins with photometric completeness below 50%. In panel d, the black solid line represents a linear fit to the observed MF, restricted to regions of the CMD where the photometric completeness exceeds 50%. The derived MF slope is indicated in the bottom-right corner of the figure. In all panels, the gray dashed line indicates the 50% completeness limit.