<s>
The	O
Rolleiflex	B-Algorithm
SL66	I-Algorithm
is	O
a	O
medium	O
format	O
single	B-Algorithm
lens	I-Algorithm
reflex	I-Algorithm
camera	I-Algorithm
made	O
by	O
Rollei	O
,	O
in	O
regular	O
production	O
from	O
1966	O
–	O
82	O
.	O
</s>
<s>
Although	O
Rollei	O
never	O
officially	O
discontinued	O
the	O
Rollei	O
SL66	O
,	O
it	O
was	O
removed	O
from	O
their	O
promotional	O
support	O
and	O
dealer	O
catalogs	O
in	O
the	O
UK	O
from	O
1976	O
and	O
for	O
all	O
intents	O
and	O
purposes	O
was	O
replaced	O
by	O
the	O
Rolleiflex	B-Algorithm
SLX	O
.	O
</s>
<s>
The	O
Rolleiflex	B-Algorithm
SL66	I-Algorithm
did	O
not	O
feature	O
in	O
Rollei	O
's	O
worldwide	O
product	O
catalog	O
in	O
1980	O
,	O
and	O
the	O
US	O
importer	O
's	O
July	O
1979	O
dealer	O
price	O
list	O
has	O
no	O
SL66	O
cameras	O
nor	O
40mm	O
,	O
250mm	O
,	O
or	O
500mm	O
lenses	O
.	O
</s>
<s>
The	O
SL66	O
represented	O
a	O
change	O
in	O
direction	O
for	O
Rollei	O
,	O
which	O
until	O
that	O
time	O
had	O
focused	O
almost	O
exclusively	O
on	O
its	O
popular	O
twin	B-Algorithm
lens	I-Algorithm
reflex	I-Algorithm
cameras	I-Algorithm
,	O
the	O
Rolleiflex	B-Algorithm
and	O
Rolleicord	B-Algorithm
.	O
</s>
<s>
In	O
1957	O
,	O
a	O
gentlemen	O
's	O
agreement	O
between	O
Reinhold	O
Heidecke	O
,	O
inventor	O
of	O
the	O
Rolleiflex	B-Algorithm
TLR	B-Algorithm
,	O
and	O
Victor	O
Hasselblad	B-Algorithm
,	O
inventor	O
of	O
the	O
Hasselblad	B-Algorithm
SLR	B-Algorithm
,	O
was	O
reached	O
to	O
ensure	O
that	O
Rollei	O
would	O
not	O
manufacture	O
SLR	B-Algorithm
cameras	I-Algorithm
,	O
and	O
Hasselblad	B-Algorithm
would	O
not	O
manufacture	O
TLR	B-Algorithm
cameras	I-Algorithm
.	O
</s>
<s>
However	O
,	O
the	O
rapid	O
adoption	O
of	O
SLRs	B-Algorithm
during	O
the	O
1960s	O
meant	O
that	O
Rollei	O
risked	O
falling	O
behind	O
in	O
this	O
market	O
at	O
a	O
time	O
when	O
demand	O
for	O
TLRs	O
was	O
decreasing	O
.	O
</s>
<s>
In	O
1964	O
plans	O
were	O
made	O
to	O
create	O
a	O
new	O
,	O
technologically	O
advanced	O
SLR	B-Algorithm
to	O
be	O
introduced	O
at	O
the	O
1966	O
photokina	O
festival	O
.	O
</s>
<s>
Like	O
the	O
Rolleiflex	B-Algorithm
TLR	B-Algorithm
and	O
the	O
Hasselblad	B-Algorithm
SLR	B-Algorithm
,	O
the	O
SL66	O
uses	O
120	O
or	O
220	O
film	O
to	O
produce	O
frames	O
of	O
6×6	O
cm	O
.	O
</s>
<s>
It	O
also	O
incorporates	O
several	O
features	O
that	O
are	O
unique	O
or	O
noteworthy	O
in	O
an	O
SLR	B-Algorithm
camera	I-Algorithm
:	O
</s>
<s>
Again	O
,	O
this	O
is	O
impossible	O
for	O
most	O
SLR	B-Algorithm
cameras	I-Algorithm
without	O
special	O
adapters	O
.	O
</s>
