Pentax SP500 SP500 Manual - Page 17

Range, light, measurement

Page 17 highlights

Range of light measurement The exposure meter of the Spotmatic measures the brightness of the ground glass. Therefore, the meter should be turned on after you have focused your subject on the ground glass. The following table shows the range of the meter's light measurement, and should not be interpreted as the camera's total range of f/stop-shutter speed combinations. As you will note from the table below, with an ASA100 film, you may use any shutter speed from 1 sec. to 1/500 sec. in combination with any aperture that will bring the meter needle to the midpoint in the viewfinder. The total range of the aperture settings is, of course, determined by the minimum and maximum apertures of the lens being used. For example, with the 55mm f/2 lens and ASA100 film, an aperture from f/2 (the maximum aperture of this lens) to f/16 (the minimum aperture) may be used with any shutter speed from 1 sec. to 1/500 sec. that will bring the meter needle to midpoint. 1 1 1 1 1 I 1 1 1 ASA B 1 2 4 8 15 30 60 125 250 500 20 • 25 32 • 40 • 50 io.64 • 80 • 125 • 160 200 • 250 • 320 400 • 500 • 640 A 800 • 1000 .1250 1600 The area A indicates the reading range of he meter. The ar a B indicates that although the shutter speed index is black and the meter needle moves, the meter is NOT operating properly. When the meter needle is centered with the shutter speed dial set at B using ASA 20-50films, this indicates that the exact shutter speed required is 2 seconds. Please expose your picture for 2 seconds. 15

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Range
of
light
measurement
The
exposure
meter
of
the
Spotmatic
measures
the
brightness
of
the
ground
glass.
Therefore,
the
meter
should
be
turned
on
after
you
have
focused
your
subject
on
the
ground
glass.
The
following
table
shows
the
range
of
the
meter's
light
measurement,
and
should
not
be
interpreted
as
the
cam-
era's
total
range
of
f/stop-shutter
speed
combinations.
As
you
will
note
from
the
table
below,
with
an
ASA100
film,
you
may
use
any
shutter
speed
from
1
sec.
to
1/500
sec.
in
combination
with
any
aperture
that
will
bring
the
meter
needle
to
the
midpoint
in
the
viewfinder.
The
total
range
of
the
aperture
settings
is,
of
course,
determined
by
the
minimum
and
max-
imum
apertures
of
the
lens
being
used.
For
example,
with
the
55mm
f/2
lens
and
ASA100
film,
an
aperture
from
f/2
(the
maximum
aperture
of
this
lens)
to
f/16
(the
minimum
aperture)
may
be
used
with
any
shutter
speed
from
1
sec.
to
1/500
sec.
that
will
bring
the
meter
needle
to
midpoint.
ASA
B
1
1
2
1
4
1
8
1
15
1
30
I
60
1
125
1
250
1
500
20
25
32
40
50
64
80
io.
125
A
160
200
250
320
400
500
640
800
1000
.1250
1600
The
area
A
indicates
the
reading
range
of
he
meter.
The
ar
a
B
indicates
that
although
the
shutter
speed
index
is
black
and
the
meter
needle
moves,
the
meter
is
NOT
operating
properly.
When
the
meter
needle
is
centered
with
the
shutter
speed
dial
set
at
B
using
ASA
20-50
films,
this
indicates
that
the
exact
shutter
speed
required
is
2
seconds.
Please
expose
your
picture
for
2
seconds.
15