The goal of this work is to provide a guideline to produce high quality chromatic contrast sensitivity (CCS) data at low frequencies, and to contrast with the previously published data. An experiment was carried out usingforced-choice stair-case method to investigate the CCS just noticeable difference (JND) in different color changing directions at different spatial frequencies. The JND ellipses at different spatial frequencies were fitted and compared with those earlier studies. The results from a white and a green center were reported. They provided theoretical basis and standard practice for the lighting and the imaging industries.