Visualization of the local approach for the estimate of the differential reddening suffered by the target star indicated with the blue asterisk. Upper left: position of NGC 2298 stars in the ACS/WFC field of view (gray points). Red circles highlight the 35 reference stars in the lower left panel. Reference stars are indicated with black crosses, among them, the 35 closest neighbours (of the target star) are marked with red circles. The lower left panel is a zoom of a 700 × 700 pixel centered on the target star. Upper right: “ordinate” vs. Δ “abscissa” for all the stars in the NGC 2298 field of view. The median Δ “abscissa” of the 35 closest neighbor is indicated by the continuous red vertical line and corresponds to the differential reddening value suffered by the target star. The histogram of the Δ “abscissa” distribution of the 35 closest neighbors is shown in the bottom right panel.