This video is about sharpness in lens design and photography. Sharpness is something we actually measure. It is represented in MTF charts and its actually a very important element to understanding the characteristics of a lens. Sharpness is essentially contrast between areas of detail. More defined contrast indicates a sharper photo. If we understand the sharpness of a lens we can also see possibilities in bokeh, field curvature, astigmatism and some types of chromatic aberration.