Nikon 5000 - Manual (Page 110)

Taking Photographs—Advanced Photography
96
Reacting Faster to Light: Sensitivity (ISO Equivalency)
What Is “Sensitivity”?
“Sensitivity” is a measure of how quickly your camera reacts to light. The higher
the sensitivity, the less light needed to make an exposure, allowing the same
exposure to be achieved with higher shutter speeds or smaller apertures. In a
film camera, sensitivity is a characteristic of the film, not the camera. The ISO
ratings you see on packages of film are a measure of their sensitivity—the higher
the ISO rating, the more sensitive the film. Higher sensitivity is achieved by
altering the chemical composition of the film, causing a random pattern, called
“grain,” to appear in the final photograph. In a digital camera, increased sen-
sitivity has a similar effect: higher sensitivities allow higher shutter speeds, at
the expense of mottling, or “noise” (the digital equivalent of film “grain”)
appearing in the final image.
Adjusting Sensitivity
In User Set A, the camera sets sensitivity automatically in response to lighting
conditions. When User Set 1, 2, or 3 is selected, you can choose a fixed value
for sensitivity from four possible settings. Sensitivity is set by rotating the com-
mand dial while pressing the ISO (
) button.
Sensitivity is displayed
in control panel and
monitor. After ISO
button is released, ISO
icon appears in control
panel when sensitivity
is above 100. At set-
ting of AUTO, AUTO is
displayed in monitor
until ISO button is re-
leased; ISO icon then
appears whenever
sensitivity is above
100.
Press while rotating
command dial
+