0

TIP500

60

D

Deliberate one-step underexposure

 

Exposure Control

 

The amount of light reaching the film plane is deter-

 

mined by a combination of the lens aperture and the

 

shutter speed. Since the two are interrelated, different

 

combinations will give the same exposure. A 1-step

 

change in the shutter speed, or a 1-stop change in the

 

aperture setting, will either halve or double the exposure.

 

For example, a shutter speed of 1/125 second passes

 

twice as much light as a setting of 1/250 second, and

 

only half as much light as a speed of 1/60 second; for an

 

aperture setting of f/11, twice as much light as f/16, and

c

half as much as f/8, is passed. This feature characterizes

the operation throughout the available range of shutter

 

5D0iP

speeds and aperture settings. With this in mind, it's easy

to see that if a correct exposure for a scene is 1 /125 at

250

f/11, then 1/60 at f/16 or 1/250 at f/8 will be equally

 

30

acceptable.

 

15The best combination for your needs will depend on the

I

results desired. Use fast shutter speeds to freeze motion,

<

2or use slow speeds to produce deliberate and creative

I

2 blur. Small apertures give greater depth of field, while

< large apertures restrict sharp focus to the main subject.

I

The creative selection of both speeds and apertures will greatly enhance your photography.

. . . and one-step overexposure,

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Image 29
Nikon EL2 instruction manual Amount of light reaching the film plane is deter