Abstract: The present invention provides a method of preparing a support for a filtration medium comprising passing a sheet of nonwoven fibrous polymeric material having first and second sides through a calender which comprises a nondeformable roll and a resilient roll, the nondeformable roll being maintained at a temperature below the melting temperature of the material, so as to increase the smoothness of the first side of the material which contacted the resilient roll. A filtration medium support material prepared in accordance with the method of the present invention, as well as a filter comprising a filtration medium and that filtration medium support material, are also provided by the present invention.