Nikon Speedlight - Page 14

SHORT-RANGE
AND
CLOSE-I'JP
For example,
if
the Nikkor
Auto
50mm
f/2
lens
is
used
with film
of
ASA
25
at
distance
of
364mm
measured
from
the
film
plane using
the extension
ring
K-l, the
table
shows
f/11
as
the
correct
aperture.
The
Exposure
Calculating
Diagram
is based
on
expo-
sure
indexes
for ASA
spee
d 25
at
l/4
reduced
power'
For combinations
other
than
ASA
25
film at
Il4
output,
use
the
f-number
indicated
by
the
Exposu
Calculating
Diagram
and
add
or
subtract
the
exposure
factor indicated
in
the
table
below
for
the combi-
nation
in use.
Note:
Use
the
f-number
engraved
on
the
lens aperture
ring.
not
the
effective
number
for
close
distances
since the
tablc
and
diagram
accommodate
the
lens extension.
For
subjects
closer
than
0.2m,
use
of
the
Macro
Ringlight
Unit SM-1
is
recommended.
Exposure
Factors
for
Film Speed
(ASAI
AssLmed as
a standard
(-1)
for the
lrght
output
1/4 and
the
f ilm
speed
ASA 25
Film
speed
(ASA}
=-'-
t*toT
Light
output
FULL
I
Light
output
1/4
25
1/4X
(Decreasa
2 stopsl
1X
32
1/5.2X
(Decrease
2-113
stoPs)
1/1.3X
(Decrease
1/3
stopl
50
1/8X
(Decrease
3
stops)
1/2X
(Decreasa
I stopl
64
1/10.4X
(Decrease
3-1/3
stopsl
1/2.6X
(Decreaso
l-l/3
stops,
100
1/16X
(Decrease
4 stopsl
1/4X
(Decrease
2 stoPsl
125
1/20.8X
(Decrease
4-113 stopsl
1/5.2X
(Decrease
2-113 stoPs)
160
1125.6x
(Decrease
4'2l3 stoPs)
1/6.4X
(Decrease
2'213
stoPsl
1L
Exposure
Calculating
Diagram
(Subject
distance
=
20Omm-6O0mm)
f-nrrb"t-_-
ASA
25
Light
output
1/4
LfiG[-ITING
500
400
300
20c
(D
=
(D
o
o
3
f
o)
m
x
€
o
ul
C
o
f
(D