We develop a digital camera model with the purpose of simulating the performance of a sky radiance colorimeter, based on a single-sensor camera equipped with a charge-coupled device imager. To provide a color image, the sensor is covered with a Bayer color filter array (CFA). The model input is the radiance, expressed in radiometric units. Demosaicking of the CFA is performed using three common interpolation methods. Color characterization is performed by calculating 3×3 matrices, based on either the maximum-ignorance assumption or computer-generated sky radiance training sets. For the model to be reliable, we incorporate multiple noise sources. We also parameterize many "critical" characteristics of the simulated imager, for example, temperature-related dark-current generation and pixel size. Error propagation analysis is performed, including an analysis for the demosaicking methods. Colorimetric performance results, expected measurement accuracy, and validation of the derived noise propagation equations are presented.