Ev Range Of The Camera; What Is Ev; Ev Range - Nikon FG-20 Instruction Manual

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EV Range of the Camera
What is EV?
Exposure value (EV) is a number representing the
available combinations of shutter speed and aperture
that give the same exposure when the scene bright -
ness and ASAIISO remain the same.
At ASAIISO 100, the combination of a one -second
shutter speed and an aperture of f/1.4 is defined as
EV 1. If the lens diaphragm is stopped down by one
full flstop or the shutter speed is one step faster, the
'EV increases by one ; if the aperture is one full flstop
wider or the shutter speed is one step slower, EV
decreases by one . Using ASA/I.SO 100 as an example ,
1 sec. at f/2 represents EV 2, 1 sec . at f/5 .6 represent s
EY 5, while 1/125 sec . at f/5.6 represents EV 12. Be-
cau se the exposure is the same , 1/30sec . at f/11 and
1/1000 sec . at fl 2 are also EV 12.
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EV range
The camera 's meter may be used only within the
meter 's EV range which determines the possible
combinations of aperture and shutter speed , depend-
ing on the film speed in use. For example, at ASA/ ISO
100, the FG-20's metering range is from EV 1 to EV 18
with an fl1.4 lens .