In this paper we use the matrix method to calculate spectacle magnification (SM) and relative spectacle magnification (RSM) using pupil magnification for myopic eyes corrected with contact lenses (CLs), and intraocular lenses (IOLs). For myopic eyes corrected with contact lenses, the calculation is very similar to the one done for myopic eyes corrected with ophthalmic lenses (OLs) since both OLs and CLs are external correcting systems. For myopic eyes corrected with intraocular lenses, the calculation is different from the ones carried out for myopic eyes with external correcting systems. In this paper we show the differences that exist between the matrix calculations for these two correcting systems, external and internal. The magnifications are calculated for specific myopic eyes corrected with CLs and IOLs. By comparing the results obtained with three correction types, namely, OLs, CLs and IOLs, we will be able to choose the best correction system for each case.