Indeed, many parameters in vision research are not accurate enough, but they are widely used in every research. One of these parameters is the visual angle; which had been considered to be static, however, it must be dynamic due to the unstoppable variations of the pupil and the lens. I therefore defined a new metric, namely, the dynamical visual angle. It is an accurate representation of the retinal areas that receive light during the variations of the pupil and the lens. Since the activation of different retinal areas produce different qualities of visual awareness, the dynamical visual angle is assume to be a measure of the quality of the visual consciousness. It's found in the following link:Preprint The Dynamical Visual Angle