The operational environment for biological research on Space Station Freedom will incorporate video for monitoring plant and animal specimens. The video coverage must include dark cycle monitoring because early experiments will utilize rodents which are nocturnal and therefore most active during the dark part of the cycle. Science requirements for monitoring during dark cycle are exacting. Infra Red (IR) or near-IR sensors are required. The trade-offs between these two sensors are based on engineering constraints, sensitivity spectrums and quality of imagery possible from either type. This paper presents results of a study conducted by the Biological Flight Research Projects Office (BFRPO) in conjunction with the Spacecraft Data Systems Branch at NASA Ames Research Center to investigate the use of CCD and IR imagery cameras to meet the science requirements. Also examined is the effect of low levels of near-IR illumination on the circadian rhythm in rodents.