for rapid material removal followed by increasingly finer abrasive grits until the desired ground finish is achieved further surface preparation is by polishing which differs from grinding by the nature of the tool wheel and the abrasive polishing is often performed with an extremely fine grit unconsolidated abrasive which is rubbed against the roll surface by a rotating cloth or elastomer wheel there are also other techniques for accomplishing the same end as the roll surface is increasingly polished an objective measure of the degree of polish becomes more obscure by prior art methods consequently such finishes are categorized by more subjective nonmenclature as 34 dull 34 34 matte 34 34 satin 34 34 mirror 34 and 34 high 34 gloss finishes these are specular gloss qualities and are more strongly influenced by the light reflective profile of the surface than by the depth and frequency of surface irregularity as measured by the standard machinist 39 s profilometer briefly specular gloss is measured by means of a glossmeter 40 fig2 which comprises a calibrated light source 41 for emitting a collimated incident beam 42 through a lens 43 and aperture 44 the beam 42 is focused on the test surface to illuminate a target area 45 of precise dimension spectural reflection 46 from the target area 45 at a predetermined angle a is collimated through an aperture 47 and focused through a lens 48 upon the sensitive surface of a photocell 49 a filter 50 may also be interposed in the light path for color compensation a shroud 51 encloses the optical components of the system to shield stray light sources the photocell power leads 52 are connected to an ammeter 53 or other measuring indicators.