<s>
The	O
Olympus	B-Algorithm
OM-1	I-Algorithm
is	O
a	O
manually	O
operated	O
35mm	O
single-lens	B-Algorithm
reflex	I-Algorithm
camera	I-Algorithm
.	O
</s>
<s>
It	O
is	O
part	O
of	O
the	O
Olympus	B-Algorithm
OM	I-Algorithm
system	I-Algorithm
.	O
</s>
<s>
The	O
first	O
model	O
was	O
presented	O
at	O
photokina	O
in	O
Cologne	O
in	O
1972	O
and	O
was	O
called	O
the	O
Olympus	B-Algorithm
M-1	I-Algorithm
.	O
</s>
<s>
Thirteen	O
years	O
earlier	O
,	O
the	O
release	O
of	O
the	O
Nikon	B-Algorithm
F	I-Algorithm
had	O
made	O
the	O
35mm	O
SLR	B-Algorithm
the	O
standard	O
choice	O
for	O
professionals	O
accustomed	O
to	O
Leica	O
and	O
other	O
rangefinders	O
,	O
but	O
it	O
had	O
driven	O
the	O
market	O
towards	O
heavy	O
and	O
bulky	O
cameras	O
.	O
</s>
<s>
The	O
Olympus	B-Algorithm
M-1	I-Algorithm
changed	O
this	O
and	O
with	O
it	O
began	O
a	O
reduction	O
of	O
size	O
,	O
weight	O
and	O
noise	O
of	O
the	O
35mm	O
SLRs	B-Algorithm
.	O
</s>
<s>
It	O
was	O
designed	O
by	O
a	O
team	O
led	O
by	O
Yoshihisa	O
Maitani	O
,	O
who	O
had	O
already	O
created	O
the	O
Pen	B-Algorithm
and	O
Pen	B-Algorithm
F	I-Algorithm
cameras	O
,	O
noted	O
for	O
their	O
compactness	O
.	O
</s>
<s>
Since	O
Leica	O
's	O
flagship	O
rangefinder	O
cameras	O
are	O
known	O
as	O
the	O
M	B-Algorithm
Series	I-Algorithm
,	O
Leica	O
complained	O
about	O
the	O
name	O
of	O
the	O
M-1	O
,	O
forcing	O
Olympus	O
to	O
rename	O
it	O
as	O
the	O
OM-1	B-Algorithm
to	O
further	O
clarify	O
between	O
the	O
brands	O
.	O
</s>
<s>
The	O
OM-1	B-Algorithm
is	O
an	O
all-mechanical	O
SLR	B-Algorithm
.	O
</s>
<s>
The	O
shutter	O
speed	O
dial	O
is	O
located	O
around	O
the	O
lens	O
mount	O
,	O
which	O
allows	O
photographers	O
to	O
keep	O
the	O
camera	O
at	O
the	O
eye	O
between	O
shots	O
more	O
easily	O
than	O
SLRs	B-Algorithm
with	O
the	O
dial	O
located	O
on	O
the	O
top	O
plate	O
.	O
</s>
<s>
Originally	O
,	O
the	O
bottom	O
plate	O
needed	O
to	O
be	O
modified	O
to	O
mount	O
a	O
motor	O
drive	O
on	O
the	O
OM-1	B-Algorithm
.	O
</s>
<s>
It	O
was	O
similar	O
to	O
the	O
OM-1MD	O
,	O
with	O
a	O
redesigned	O
film	O
advance	O
lever	O
,	O
a	O
flash	O
ready/sufficient	O
flash	O
LED	O
in	O
the	O
viewfinder	O
,	O
and	O
automatic	O
flash	O
synchronization	O
(	O
X-sync	O
)	O
,	O
regardless	O
of	O
the	O
position	O
of	O
the	O
FP/X	O
switch	O
when	O
used	O
with	O
a	O
T-series	O
flash	O
unit	O
mounted	O
on	O
Flash	B-Algorithm
Shoe	I-Algorithm
4	O
.	O
</s>
<s>
Professional	O
photographers	O
who	O
used	O
the	O
OM-1	B-Algorithm
include	O
Patrick	O
Lichfield	O
,	O
Jane	O
Bown	O
,	O
David	O
Bailey	O
,	O
Josef	O
Koudelka	O
,	O
Chris	O
Bonington	O
,	O
and	O
Kate	O
Garner	O
.	O
</s>
