Sekonic Studio Deluxe L-28 C2 - Lighting Contrast Control (Indoors); Outdoor Contrast Control

5'2'
Lighting
Gontrast
Gontrol
(lndoors)
Lighting
contrast
control
is
necess
ary in
order
to
measure
the
m
a
in
a
nd f
ill-in
lights
directed
at
a
subject.
when
the
intensity
of
these
lights
is
known,
the
photographer
can
change
and
control
the
ratio
between
them for
whatever
effects
he
wishes
to
achieve.
He
can also
duplicate
this
lighting
contrast
at
some
future
time.
To
measure
contrast:
(1)
Replace
Lumisphere
with
Lumidisk
(2)
Switch
on
on
ty
the
m
a
in
(key)
tight
(3)
From
the
subject position
poinl'the
Lumidisk
direcily
at
the
main
lignt,
a
nd
read
out
the
foot-ca
ndles
registered
on
the
meter.
(4)
Turn
on
the
fill-in
rights,
ancJ
point
the
Lumidisk
directly
at
them
from
the
subject position.
when
measuring
the
fill-in
lights,
be
sure
to
shade
the
Lumidisk
from
the
main
light.
(5)
Divide
the
intensity
of
th;
main tight
by
that of
the
fill-in
lights
to
fincl
the
contrast
ratio
(light
balance).
Exa
m
ple
:
The
main
light
reads
500
Fill.in
lights
read
ZSO
Lighting
contrast
ratio
-
49
-
Zo,
Z to 1
250
1
1",'
(6)
lf
the
lighting
contrast
ratio
is
not
as
desired, the
f
ill-in
lights
m
ust
be
readjusted.
(7)
when
the
proper
ratio
is
found,
the
Lumidisl<
ca
n
be
replaced
by
the
Lumisphere.
Now
the
exposure
can
be
determined
in
the
usual
way.
Note:
In
a
fully'equipped
studio
it
is
suggested
that
for
the
best
results
you
keep
the
lighti;a
con-
trast
ratio
between
Z
to
1
and
4
to
1.
5-3.
Outdoor Gontrast
Gontrol
Lightirrg
ca
n
be measured
a
nd controlled
outdoors
with
the
same
precision
as in
a
studio.
The
procedure
is
a
lmost
exactly
the
sa me.
White
or
silver-f
aced reflectors
are
used to
brighten those
sides
of
a
subject
which
are
in
shadow.
place
the
Lumidisk
in
the
meter
and take
a reading
when it
is
directed
towards
the
sun.
Now
take
another
reading
with
the
Lumidisk
turned
towards
the
reftectors,
making
certa in
to shield
the Lumidisk
with
your
ha
nd
from
the
direct
rays
of the
sun. You
now
know
the intensity
of
both
lights
and can
control
their
ratio
by rearranging
the
reflectors.
For
best
results
in
color
photography,
the
fill-in light
should
be from
Llz
to
Ll4
that
of
the
m
a
in light.
Dramatic
black
and
wlrite
effects
can
be
achieved
by
using a
higher
ratio,
such
as
having
the
reflected
lights
as
f ittle
as
LILG
the
sunlight
intensity.
Note:
when
the needle
moves
outside
the
scale
(because
of
bright lieht) use the
HIGH
Slide.
To
obtain
foot-candles
(lieht
intensity)
with
the
HIGH
Stide,
the
number
indicated
by
ine
needfe
must
be multiplied
by
32,
(as
explained
in 2-3).
The
liehting
contrast ratio
can
be
obtained
readily
by
computing
the
relative
intensity of
the
main
lieht
and
the
fill-in
tights,
(as
ex.
plained
in
5-2).
whe,n the
proper
ratio
has
been
obtained,
replace
the
Lumidisk
with
the Lumisphere
and
determine
the
exposure
as
usuat.
Be
sure that all the
light
from
the
sun
and
ref
lectors
falls
upon
the
Lumisphere.
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