Image based measurement techniques are increasingly used to perform multi-directional reflectance measurements of objects/materials. In these techniques, commercially available colour (RGB) cameras are used along with the monochrome CCD cameras to measure the radiance reflected from the object/material surface at multiple reflection directions. The data acquired through these cameras is used to estimate the BRDF of given sample/material. This paper presents an image-based method to measure the reflectance of the sample material using the camera spectral sensitivities. A multi-angle measurement setup described in previous studies was used to perform the measurements. A reflection model of the sample was derived in a colorimetric space using the Phong model. Camera spectral sensitivities were measured using a Bentham monochromator to build a tranformation from Camera RGB to CIEXYZ colour space. A reflection model was fitted in the colorimetric domain (CIEXYZ) for the sample materials used. Results show that image based multi-directional reflectance measurements can be performed using the camera spectral sensitivities.