The study of the influence of the aperture size over the measurements of the L*a*b chromatic coordinates in spectrocolorimeters, in particular, the Macbeth 7000A ® spectrocolorimeter with an illumination/detection geometry d/8°. This is of importance due to the fact that many industry laboratories use it. This study will give us an invaluable insight of the variations in the measurements of the chromatic coordinates in the visible spectrum range regarding to three different aperture sizes; 2,5cm (AL), 1cm (AM), and 0,5cm (AS). The measurements are carried out on 13 Reference Materials (RMs) or diffusers with different hue under the following metrics; including specular component (SCI), excluding ultraviolet component (UVex), D65 illuminant, and 2° observer. The analysis and quantification of the data were done by the use of statistical tools such as variance analysis and Mendel parameters. In this work the analysis of the latter measurements as well as the methodology that quantifies the accuracy and precision of the method, i.e., repeatability and reproducibility, are presented.