Color and trash meters, similar to those used in the high volume instrument (HVI) system, were installed in the microgin at the United States Department of Agriculture (USDA), U. S. Cotton Ginning Laboratory, Stoneville, MS. Cotton color (Rd and +b) and trash measurements from these meters were compared to data obtained at a USDA, Agricultural Marketing Service (AMS), Cotton Division, Cotton Classing Office (CO). Data were compared for ceramic tiles, stationary cotton (such as is done at the CO), and cotton samples obtained automatically while ginning. Temperature changes and vibration of the measurement heads were added to further simulate conditions in the gin. Results indicated that 1) an ambient temperature range of ±11°C (±20°F) from the reference temperature gave acceptable data, 2) the drift with time of Rd and +b was low and no drift of trash readings was measured, 3) vibration had no adverse affect on the measurements, 4) no differences in measurements of color or trash occurred between the gin based equipment and the classing office when the samples were presented manually, 5) Rd and percent area were consistently lower for automated sampling, and 6) +b was not different for automated sampling than for samples measured at the CO.