<s>
The	O
Canon	B-Algorithm
AV-1	I-Algorithm
is	O
a	O
35	O
mm	O
single-lens	B-Algorithm
reflex	I-Algorithm
camera	I-Algorithm
with	O
an	O
FD	B-Algorithm
lens	I-Algorithm
mount	I-Algorithm
,	O
introduced	O
by	O
Canon	O
Inc	O
.	O
in	O
1979	O
.	O
</s>
<s>
The	O
AV-1	B-Algorithm
is	O
very	O
similar	O
to	O
the	O
1976	O
AE-1	B-Algorithm
but	O
provides	O
aperture	B-Algorithm
priority	I-Algorithm
autoexposure	O
rather	O
than	O
the	O
AE-1	B-Algorithm
'	O
s	O
shutter	B-Algorithm
speed	I-Algorithm
priority	I-Algorithm
AE	O
.	O
</s>
<s>
Canon	O
's	O
international	O
distributors	O
,	O
particularly	O
in	O
the	O
United	O
States	O
,	O
had	O
clamored	O
for	O
such	O
a	O
camera	O
because	O
competing	O
brands	O
offered	O
mostly	O
aperture-priority	B-Algorithm
cameras	O
and	O
some	O
preferred	O
it	O
.	O
</s>
<s>
The	O
AV	O
in	O
the	O
name	O
referred	O
to	O
the	O
type	O
of	O
autoexposure	O
;	O
Av	O
(	O
Aperture	O
Value	O
)	O
is	O
a	O
common	O
abbreviation	O
for	O
aperture	B-Algorithm
priority	I-Algorithm
.	O
</s>
<s>
This	O
is	O
called	O
the	O
New	O
FD	B-Algorithm
mount	I-Algorithm
and	O
does	O
away	O
with	O
the	O
older	O
type	O
of	O
mounting	O
ring	O
which	O
was	O
fitted	O
on	O
to	O
the	O
rear	O
of	O
the	O
lens	O
and	O
was	O
awkward	O
to	O
use	O
and	O
needed	O
two	O
hands	O
,	O
to	O
a	O
newer	O
,	O
easier	O
system	O
whereby	O
the	O
user	O
lined	O
up	O
the	O
red	O
dot	O
on	O
the	O
lens	O
,	O
with	O
the	O
red	O
dot	O
on	O
the	O
camera	O
and	O
simply	O
turned	O
the	O
whole	O
lens	O
clockwise	O
until	O
it	O
clicked	O
into	O
place	O
.	O
</s>
<s>
All	O
the	O
other	O
AE-1	B-Algorithm
accessories	O
fit	O
the	O
AV-1	B-Algorithm
.	O
</s>
