<s>
The	O
Nikon	B-Algorithm
was	O
the	O
first	O
camera	O
introduced	O
by	O
the	O
optical	O
manufacturer	O
Nippon	O
Kogaku	O
KK	O
.	O
</s>
<s>
It	O
is	O
a	O
35mm	O
rangefinder	B-Algorithm
camera	I-Algorithm
,	O
in	O
retrospect	O
known	O
as	O
the	O
Nikon	B-Algorithm
I	O
.	O
</s>
<s>
The	O
original	O
Nikon	B-Algorithm
I	O
,	O
as	O
introduced	O
in	O
1948	O
,	O
had	O
no	O
flash	O
synchronisation	O
,	O
but	O
was	O
otherwise	O
a	O
fully-fledged	O
up-to-date	O
rangefinder	B-Algorithm
camera	I-Algorithm
.	O
</s>
<s>
The	O
designers	O
chose	O
the	O
24	O
×	O
32mm	O
frame	O
size	O
pioneered	O
by	O
the	O
Minolta	B-Algorithm
35	I-Algorithm
launched	O
a	O
year	O
earlier	O
by	O
Chiyoda	O
Kogaku	O
,	O
known	O
as	O
the	O
Nippon	O
format	O
,	O
which	O
yielded	O
more	O
frames	O
per	O
length	O
of	O
film	O
,	O
and	O
matched	O
more	O
closely	O
the	O
common	O
paper	O
sizes	O
.	O
</s>
<s>
In	O
consequence	O
,	O
the	O
Nikon	B-Algorithm
M	O
was	O
introduced	O
in	O
the	O
autumn	O
1949	O
.	O
</s>
<s>
This	O
was	O
the	O
Nikon	B-Algorithm
S	I-Algorithm
,	O
long	O
overdue	O
when	O
made	O
available	O
early	O
in	O
1951	O
;	O
it	O
is	O
a	O
Nikon	B-Algorithm
M	O
with	O
flash	O
sync	O
contacts	O
,	O
two	O
sockets	O
at	O
the	O
upper	O
left-hand	O
edge	O
of	O
the	O
body	O
.	O
</s>
<s>
All	O
cameras	O
sold	O
with	O
this	O
feature	O
are	O
considered	O
a	O
Nikon	B-Algorithm
S	I-Algorithm
by	O
the	O
factory	O
,	O
even	O
if	O
marked	O
M	O
,	O
though	O
collectors	O
do	O
distinguish	O
these	O
as	O
more	O
valuable	O
than	O
the	O
S	O
.	O
The	O
Nikon	B-Algorithm
S	I-Algorithm
sold	O
well	O
,	O
and	O
became	O
the	O
first	O
Nikon	B-Algorithm
imported	O
to	O
the	O
US	O
market	O
.	O
</s>
<s>
A	O
number	O
of	O
Nikon	B-Algorithm
S	I-Algorithm
cameras	O
have	O
one	O
more	O
serial	O
number	O
digit	O
,	O
known	O
as	O
the	O
8-digit	O
Nikon	B-Algorithm
S	I-Algorithm
.	O
When	O
reaching	O
6099999	O
the	O
engraver	O
continued	O
at	O
60910000	O
,	O
but	O
it	O
was	O
soon	O
realized	O
that	O
the	O
long	O
serial	O
number	O
was	O
impractical	O
,	O
and	O
after	O
some	O
1200	O
cameras	O
,	O
the	O
numbering	O
reverted	O
to	O
6100000	O
.	O
</s>
<s>
Several	O
further	O
Nikon	B-Algorithm
rangefinder	B-Algorithm
models	O
were	O
introduced	O
throughout	O
the	O
1950s	O
:	O
the	O
S2	O
,	O
S3	O
,	O
S4	O
,	O
and	O
SP	O
.	O
</s>
<s>
The	O
latter	O
three	O
were	O
built	O
on	O
the	O
same	O
frame	O
with	O
different	O
features	O
;	O
the	O
Nikon	B-Algorithm
F	I-Algorithm
SLR	O
shares	O
the	O
basic	O
body	O
configuration	O
of	O
the	O
latest	O
rangefinder	B-Algorithm
models	O
.	O
</s>
