Objective: The aims of this study are to 1) examine the sensitivity of the Cambridge Color Test (CCT) and the low vision CCT (LvCCT) to the severity of retinal disease in inherited retinal degeneration (IRD) by comparing color vision status with changes in photoreceptor structure and function, 2) examine the effects of eccentric fixation and reduction in visual acuity on color discrimination thresholds obtained with the CCT and LvCCT, and 3) establish normal ranges for the CCT and the LvCCT and determine the intra-session and inter-session variabilities for these tests.