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Lens
> Lens controls > Aperture
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TOP:
Your eye at night. The pupil opens
to gather as much light as possible.
BELOW: Your eye on a sunny day. The
pupil gets small to shut out excess
light.
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Most
lenses have three basic controls. We will look at all
three.
Aperture:
"Aperture" (or "f-stop")
refers to the opening at the base of the lens that determines
how much light enters the camera.
Ever
notice how your pupil gets smaller when you go outside
in a bright sunny day? And then gets big on a moonlit
night? Check this out on a friend. Outside, their pupil
(the black part of their eye) gets tiny--the size of
a pinpoint!. Indoors, it's huge--the size of a pea!
That's
because in the darkish indoors, the pupil opens up to
"grab" as much light as it can. In the bright
outdoors, your pupil gets small to cut down on the excess
light.
Think
of this example: what do you do on a real sunny day
at the beach? You squint. You are trying to minimize
the light hitting your eye. (It's easier if you have
big bushy eyebrows, like me). Similarly, at the beach,
your pupil gets small because it need to minimize the
light entering our eyes.
The
cool thing is that your pupil automatically adjusts
to the incoming light all day long.
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