Log magnification ﹩{{\rm{log}}}_{10}\mu ﹩ as a function of source position β for the images in the three-image zone. The magnification of the subimages created around the lens (solid and dashed lines) depends strongly on the lens amplitude A, indicated by different colors, whereas the magnification of the main image (dashed–dotted lines) remains around unity. The point mass lens has no outer caustic and a different dependence of the subimage magnification on the lens amplitude due to the singularity in the lens potential. Both the Gaussian and the top-hat models create a pair of subimages around the lens, which may not be separable due to their close positions. The magnification curves of the subimage dominant in magnification for both the Gaussian and the top-hat models can be normalized into a unified form (see Figure 6).