This study reports the optical properties of two different polymers, polystyrene (PS) and tetra methyl polycarbonate (TMPC) over a wide range of casting conditions. Two distinct casting methods are used, free casting (FC) and blade casting (BC). The casting process induces significant levels of molecular order in the produced films, leading to birefringence. It is shown that the level of induced birefringence depends on the optical properties of the polymer, the casting conditions, casting temperature and the type of solvent used. Films produced by the FC method are less birefringent than those produced by the BC method. It is also shown that blending of miscible polymers with opposite optical anisotropies can be exploited to produce non-birefringent films.