Now, look through the viewfinder.
On the bottom, there are small
weather symbols that correspond
to your Aperture setting. The
aperture is an iris-like opening in
the lens which regulates the light
admitted through it. Move the
Aperture Selection (17) to the
weather symbol that most
resembles your outside condition -
full sun (f/16), partial sun (f/11), light
clouds (f/8), heavy clouds (f/5.6), or
overcast (f/4). You now have the
correct exposure for a daytime shot!