1 The Director of Photography – an overview

Lenses 51
Figure 5.1 The relationship
between resolution and contrast
Let us look at some of the sharpness we perceive in a scene as
against the actual resolution of the image. In Figure 5.1, we have two
nearly identical images. Don’t study them too carefully, but at a glance
which do you think is the sharper? I would guess you chose the bottom
one. Wrong! All the images for this example were taken on my Nikon
CoolPix camera; the top picture was downloaded at 300 dots per inch
(DPI) and the lower picture at 75 DPI. The difference is the top picture,
at the higher resolution, has a much lower contrast than the bottom
picture – contrast has fooled you into thinking the resolution is
higher when the contrast is higher.