<s>
The	O
Nikon	B-Algorithm
FG-20	I-Algorithm
is	O
a	O
35	O
mm	O
film	O
single-lens	B-Algorithm
reflex	I-Algorithm
(	O
SLR	B-Algorithm
)	O
camera	O
with	O
interchangeable	O
lenses	O
.	O
</s>
<s>
It	O
was	O
released	O
in	O
1984	O
by	O
Nippon	O
Kogaku	O
K	O
.	O
K	O
.	O
(	O
now	O
the	O
Nikon	O
Corporation	O
)	O
as	O
the	O
successor	O
to	O
the	O
earlier	O
EM	B-Algorithm
and	O
FG	B-Algorithm
cameras	O
.	O
</s>
<s>
It	O
is	O
actually	O
a	O
downgrade	O
from	O
its	O
most	O
direct	O
predecessor	O
,	O
the	O
FG	B-Algorithm
,	O
lacking	O
the	O
FG	B-Algorithm
's	O
program	O
auto	O
exposure	O
mode	O
.	O
</s>
<s>
It	O
uses	O
the	O
same	O
vertical-travel	O
metal	O
focal-plane	O
shutter	O
as	O
the	O
FG	B-Algorithm
,	O
with	O
electronically	O
timed	O
speeds	O
from	O
1	O
to	O
1/1000	O
second	O
as	O
well	O
as	O
bulb	O
and	O
a	O
mechanically	O
timed	O
1/90	O
-second	O
speed	O
.	O
</s>
<s>
The	O
FG-20	O
could	O
be	O
considered	O
a	O
variant	O
of	O
the	O
FG	B-Algorithm
,	O
as	O
the	O
differences	O
between	O
the	O
two	O
are	O
the	O
omission	O
of	O
program	O
mode	O
,	O
exposure	O
compensation	O
dial	O
,	O
and	O
TTL/OTF	O
flash	O
metering	O
from	O
the	O
FG	B-Algorithm
.	O
</s>
