<s>
This	O
article	O
discusses	O
the	O
cameras	O
mainly	O
35	O
mm	O
SLRs	B-Algorithm
manufactured	O
by	O
Ricoh	O
Imaging	O
Corp	O
.	O
and	O
its	O
predecessors	O
,	O
and	O
.	O
</s>
<s>
Pentax	B-Application
must	O
not	O
be	O
confused	O
with	O
Pentax	B-Algorithm
6x7	I-Algorithm
or	O
Pentax	B-Algorithm
67	I-Algorithm
which	O
are	O
120	O
medium	O
format	O
6x7cm	O
film	O
cameras	O
.	O
</s>
<s>
It	O
covers	O
from	O
the	O
first	O
"	O
Asahiflex	B-Algorithm
"	O
models	O
in	O
1952	O
and	O
their	O
successor	O
,	O
the	O
pivotal	O
"	O
Asahi	B-Algorithm
Pentax	I-Algorithm
"	O
single-lens	B-Algorithm
reflex	I-Algorithm
camera	I-Algorithm
,	O
last	O
made	O
in	O
1997	O
,	O
to	O
the	O
present	O
time	O
known	O
as	O
"	O
Pentax	B-Application
"	O
first	O
made	O
in	O
1981	O
.	O
</s>
<s>
The	O
Korean	O
War	O
saw	O
a	O
huge	O
influx	O
of	O
journalists	O
and	O
photographers	O
to	O
the	O
Far	O
East	O
,	O
where	O
they	O
were	O
impressed	O
by	O
lenses	O
from	O
companies	O
such	O
as	O
Nikon	B-Algorithm
and	O
Canon	O
for	O
their	O
Leica	O
rangefinder	O
cameras	O
,	O
and	O
also	O
by	O
bodies	O
by	O
these	O
and	O
other	O
companies	O
to	O
supplement	O
and	O
replace	O
the	O
Leica	O
and	O
Contax	O
cameras	O
they	O
were	O
using	O
.	O
</s>
<s>
1971	O
:	O
The	O
world	O
's	O
first	O
SLR	B-Algorithm
camera	I-Algorithm
with	O
a	O
TTL	O
automatic-exposure	O
control	O
.	O
</s>
<s>
1995	O
:	O
The	O
world	O
's	O
smallest	O
autofocus	O
SLR	B-Algorithm
camera	I-Algorithm
designed	O
based	O
on	O
the	O
concept	O
of	O
"	O
intuitive	O
operation	O
"	O
is	O
launched	O
.	O
</s>
<s>
1997	O
:	O
The	O
world	O
's	O
first	O
autofocus	O
medium	O
format	O
SLR	B-Algorithm
camera	I-Algorithm
.	O
</s>
<s>
2008	O
:	O
The	O
world	O
's	O
smallest	O
digital	B-Device
SLR	I-Device
camera	I-Device
equipped	O
with	O
an	O
image	O
sensor	O
equivalent	O
to	O
the	O
APS-C	B-Algorithm
size	O
format	O
is	O
launched	O
.	O
</s>
<s>
2010	O
:	O
The	O
world	O
's	O
first	O
to	O
introduce	O
a	O
digital	O
medium	O
format	O
SLR	B-Algorithm
camera	I-Algorithm
.	O
</s>
<s>
2012	O
:	O
The	O
world	O
's	O
first	O
medium	O
format	O
DSLR	B-Device
without	O
IR	O
cut	O
filter	O
especially	O
for	O
research	O
,	O
archival	O
,	O
and	O
law	O
enforcement	O
use	O
.	O
</s>
<s>
2012	O
:	O
The	O
first	O
mirrorless	B-Device
camera	I-Device
to	O
natively	O
support	O
a	O
SLR	B-Algorithm
lens	O
lineup	O
.	O
</s>
<s>
2016	O
:	O
Pentax	B-Application
was	O
the	O
first	O
to	O
introduce	O
a	O
weather	O
resistant	O
and	O
backside	O
illuminated	O
flexible	O
tilt	O
type	O
LCD	B-Device
monitor	O
with	O
their	O
first	O
professional	O
full	B-Algorithm
frame	I-Algorithm
DSLR	I-Algorithm
.	O
</s>
<s>
Its	O
designers	O
were	O
convinced	O
of	O
the	O
inherent	O
superiority	O
of	O
the	O
SLR	B-Algorithm
and	O
so	O
proceeded	O
along	O
these	O
lines	O
.	O
</s>
<s>
This	O
effort	O
resulted	O
in	O
the	O
Asahiflex	B-Algorithm
I	I-Algorithm
,	O
which	O
was	O
also	O
the	O
first	O
Japanese	O
35mm	O
SLR	B-Algorithm
.	O
</s>
<s>
In	O
the	O
case	O
of	O
the	O
Asahiflex	B-Algorithm
,	O
study	O
should	O
be	O
made	O
of	O
the	O
immediate	O
pre-war	O
and	O
immediate	O
post-war	O
models	O
of	O
the	O
Praktiflex	O
,	O
which	O
could	O
be	O
properly	O
called	O
the	O
inspiration	O
for	O
the	O
Asahiflex	B-Algorithm
.	O
</s>
<s>
According	O
to	O
other	O
sources	O
,	O
it	O
was	O
a	O
pre-war	O
Reflex	O
Corelle	O
,	O
owned	O
by	O
president	O
Mr.	O
Matsumoto	O
,	O
that	O
inspired	O
the	O
Asahiflex	B-Algorithm
.	O
</s>
<s>
The	O
Asahiflex	B-Algorithm
I	I-Algorithm
had	O
a	O
non-interchangeable	O
waist-level	O
viewfinder	O
,	O
with	O
a	O
direct	O
optical	O
viewfinder	O
for	O
eye-level	O
use	O
.	O
</s>
<s>
The	O
Asahiflex	B-Algorithm
I	I-Algorithm
had	O
a	O
non-returning	O
mirror	O
and	O
shutter	O
speeds	O
from	O
1/25	O
to	O
1/500	O
.	O
</s>
<s>
The	O
problem	O
of	O
mirror	O
black-out	O
was	O
one	O
of	O
the	O
main	O
problems	O
with	O
prior	O
SLR	B-Algorithm
designs	O
,	O
greatly	O
reducing	O
usability	O
and	O
a	O
major	O
reason	O
for	O
the	O
greater	O
popularity	O
of	O
the	O
rangefinder	O
.	O
</s>
<s>
With	O
the	O
final	O
model	O
in	O
the	O
series	O
,	O
the	O
IIA	O
,	O
the	O
Asahiflex	B-Algorithm
gained	O
slow	O
speeds	O
from	O
1/25th	O
of	O
a	O
second	O
to	O
1/2	O
of	O
a	O
second	O
.	O
</s>
<s>
A	O
recognized	O
problem	O
with	O
the	O
Asahiflex	B-Algorithm
series	O
was	O
that	O
,	O
lacking	O
a	O
pentaprism	O
,	O
it	O
was	O
very	O
difficult	O
to	O
use	O
the	O
camera	O
in	O
a	O
vertical	O
position	O
and	O
taking	O
pictures	O
of	O
moving	O
objects	O
was	O
almost	O
impossible	O
.	O
</s>
<s>
In	O
1957	O
,	O
Asahi	O
introduced	O
the	O
Pentax	B-Application
series	O
,	O
a	O
35	O
mm	O
single-lens	B-Algorithm
reflex	I-Algorithm
camera	I-Algorithm
(	O
SLR	B-Algorithm
)	O
camera	O
which	O
was	O
so	O
well	O
received	O
that	O
it	O
influenced	O
the	O
design	O
of	O
35mm	O
SLRs	B-Algorithm
worldwide	O
for	O
years	O
to	O
come	O
.	O
</s>
<s>
The	O
Pentax	B-Application
and	O
its	O
later	O
development	O
and	O
likewise	O
classic	O
1964	O
Pentax	B-Algorithm
Spotmatic	I-Algorithm
spurred	O
the	O
development	O
of	O
Asahi	O
into	O
a	O
photographic	O
multinational	O
company	O
,	O
eventually	O
renaming	O
itself	O
"	O
Pentax	B-Application
"	O
after	O
its	O
seminal	O
product	O
.	O
</s>
<s>
The	O
Pentax	B-Application
series	O
remains	O
pivotal	O
in	O
the	O
development	O
of	O
modern	O
SLR	B-Algorithm
photography	O
.	O
</s>
<s>
It	O
's	O
known	O
that	O
the	O
"	O
Pentax	B-Application
"	O
name	O
was	O
originally	O
registered	O
as	O
a	O
trademark	O
by	O
VEB	O
Pentacon	O
,	O
duly	O
noting	O
that	O
both	O
the	O
M42	B-Algorithm
lens	I-Algorithm
mount	I-Algorithm
and	O
the	O
first	O
recognizably	O
modern	O
35mm	O
SLR	B-Algorithm
camera	I-Algorithm
,	O
the	O
Contax	O
D	O
,	O
were	O
products	O
of	O
the	O
East	O
German	O
branch	O
of	O
Zeiss	O
Ikon	O
,	O
circa	O
1949	O
.	O
</s>
<s>
In	O
fact	O
the	O
name	O
Pentax	B-Application
comes	O
from	O
a	O
contraction	O
of	O
PENTAprism	O
and	O
AsahifleX	B-Algorithm
.	O
</s>
<s>
The	O
Asahi	B-Algorithm
Pentax	I-Algorithm
of	O
1957	O
featured	O
:	O
</s>
<s>
Earlier	O
35mm	O
SLRs	B-Algorithm
,	O
with	O
the	O
exception	O
of	O
Exakta	O
's	O
left-handed	O
lever	O
,	O
and	O
the	O
Edixa	B-Algorithm
Reflex	I-Algorithm
,	O
had	O
knob	O
advance	O
.	O
</s>
<s>
Film	O
rewind	O
crank	O
,	O
likewise	O
a	O
first	O
for	O
35mm	O
SLRs	B-Algorithm
.	O
</s>
<s>
Moreover	O
,	O
the	O
Pentax	B-Application
placed	O
controls	O
in	O
locations	O
that	O
would	O
become	O
standard	O
on	O
35mm	O
SLRs	B-Algorithm
from	O
all	O
manufacturers	O
,	O
such	O
as	O
the	O
right-handed	O
rapid	O
wind	O
lever	O
,	O
the	O
bottom	O
right	O
mounted	O
rewind	O
release	O
,	O
and	O
film	O
speed	O
reminder	O
around	O
the	O
film	O
rewind	O
crank	O
.	O
</s>
<s>
The	O
photographic	O
giants	O
Canon	O
&	O
Nikon	B-Algorithm
,	O
did	O
not	O
introduce	O
their	O
own	O
SLR	B-Algorithm
cameras	I-Algorithm
until	O
1959	O
with	O
the	O
Canonflex	O
and	O
the	O
F-series	B-Algorithm
respectively	O
.	O
</s>
<s>
By	O
contrast	O
,	O
the	O
Pentax	B-Application
series	O
offered	O
these	O
features	O
at	O
a	O
relatively	O
low	O
price	O
,	O
introducing	O
many	O
photographers	O
to	O
35mm	O
SLR	B-Algorithm
photography	O
.	O
</s>
<s>
The	O
Asahi	B-Algorithm
Pentax	I-Algorithm
series	O
went	O
through	O
various	O
iterations	O
until	O
1964	O
.	O
</s>
<s>
The	O
camera	O
excited	O
tremendous	O
attention	O
and	O
in	O
1964	O
the	O
first	O
production	O
Spotmatic	B-Algorithm
(	O
hyphen	O
dropped	O
)	O
emerged	O
.	O
</s>
<s>
The	O
Spotmatic	B-Algorithm
was	O
virtually	O
identical	O
to	O
the	O
prototype	O
;	O
however	O
,	O
the	O
spotmeter	O
was	O
replaced	O
with	O
an	O
all-over	O
average-reading	O
exposure	O
meter	O
in	O
order	O
to	O
give	O
more	O
consistent	O
results	O
.	O
</s>
<s>
The	O
Spotmatic	B-Algorithm
was	O
replaced	O
by	O
the	O
Spotmatic	B-Algorithm
II	O
with	O
many	O
upgrades	O
1971	O
-	O
1976	O
.	O
</s>
<s>
In	O
1966	O
Asahi	O
Optical	O
had	O
produced	O
one	O
million	O
SLR	B-Algorithm
cameras	I-Algorithm
since	O
the	O
first	O
Asahiflex	B-Algorithm
of	O
1962	O
.	O
</s>
<s>
During	O
the	O
Spotmatic	B-Algorithm
era	O
Asahi	O
were	O
manufacturing	O
more	O
SLRs	B-Algorithm
per	O
month	O
than	O
all	O
the	O
other	O
camera	O
manufacturers	O
combined	O
.	O
</s>
<s>
One	O
of	O
the	O
technological	O
highlights	O
was	O
the	O
Electro-Spotmatic	O
of	O
1971	O
.	O
</s>
<s>
The	O
series	O
concluded	O
in	O
1973	O
with	O
the	O
introduction	O
of	O
the	O
Spotmatic	B-Algorithm
F	O
(	O
now	O
incorporating	O
open-aperture	O
metering	O
rather	O
than	O
the	O
stop-down	O
metering	O
of	O
the	O
early	O
models	O
)	O
.	O
</s>
<s>
However	O
,	O
by	O
the	O
mid-1970s	O
the	O
limitations	O
of	O
the	O
M42	B-Algorithm
mount	I-Algorithm
were	O
being	O
felt	O
.	O
</s>
<s>
It	O
was	O
a	O
great	O
step	O
for	O
Asahi	O
Optical	O
to	O
take	O
but	O
the	O
M42	B-Algorithm
screw	I-Algorithm
mount	I-Algorithm
,	O
by	O
now	O
widely	O
known	O
as	O
'	O
Pentax	B-Algorithm
screw	I-Algorithm
mount	I-Algorithm
 '	O
,	O
had	O
reached	O
the	O
end	O
of	O
its	O
useful	O
life	O
.	O
</s>
<s>
Pentax	B-Application
were	O
now	O
to	O
adopt	O
the	O
K-mount	B-Algorithm
that	O
would	O
see	O
them	O
through	O
the	O
next	O
40	O
years	O
.	O
</s>
<s>
In	O
1960	O
,	O
the	O
same	O
year	O
that	O
Asahi	O
Optical	O
introduced	O
the	O
Spot-matic	O
prototype	O
at	O
photokina	O
,	O
they	O
also	O
showed	O
another	O
SLR	B-Algorithm
prototype	O
which	O
they	O
called	O
the	O
Metallica	O
.	O
</s>
<s>
The	O
Metallica	O
gave	O
a	O
glimpse	O
into	O
the	O
future	O
direction	O
of	O
Pentax	B-Application
cameras	I-Application
;	O
it	O
featured	O
a	O
prototype	O
bayonet	O
lens	O
mount	O
,	O
a	O
vertical-traveling	O
,	O
metallic	O
Copal-type	O
focal	O
plane	O
shutter	O
(	O
from	O
which	O
the	O
camera	O
drew	O
its	O
name	O
)	O
,	O
and	O
an	O
already	O
obsolescent	O
coupled	O
selenium	O
light	O
meter	O
.	O
</s>
<s>
The	O
metering	O
system	O
,	O
for	O
the	O
first	O
time	O
in	O
a	O
35mm	O
SLR	B-Algorithm
,	O
controlled	O
the	O
shutter	O
speed	O
automatically	O
based	O
on	O
the	O
aperture	O
set	O
.	O
</s>
<s>
With	O
these	O
innovative	O
developments	O
,	O
the	O
Metallica	O
pioneered	O
features	O
that	O
would	O
not	O
surface	O
on	O
Pentax	B-Application
production	O
cameras	O
until	O
the	O
Electro-Spotmatic	O
(	O
ES	O
)	O
(	O
automatic	O
aperture-priority	B-Algorithm
exposure	O
)	O
in	O
1971	O
and	O
K2	O
(	O
vertical	O
metal	O
shutter	O
,	O
bayonet	O
lens	O
mount	O
,	O
automatic	O
aperture-priority	B-Algorithm
exposure	O
)	O
in	O
1975	O
.	O
</s>
<s>
The	O
K2	O
DMD	O
and	O
K1000	B-Algorithm
followed	O
in	O
1976	O
.	O
</s>
<s>
What	O
set	O
these	O
cameras	O
apart	O
from	O
earlier	O
Pentax	B-Application
ones	O
was	O
the	O
replacement	O
of	O
the	O
M42	O
"	O
universal	O
"	O
screw-lens	O
mount	O
with	O
a	O
proprietary	O
bayonet	O
mount	O
system	O
,	O
known	O
as	O
the	O
K	B-Algorithm
mount	I-Algorithm
.	O
</s>
<s>
Still	O
the	O
basis	O
for	O
Pentax	B-Application
lenses	O
and	O
cameras	O
today	O
,	O
the	O
K	B-Algorithm
mount	I-Algorithm
offered	O
greater	O
convenience	O
and	O
enabled	O
the	O
production	O
of	O
faster	O
lenses	O
such	O
as	O
the	O
50mm	O
.	O
</s>
<s>
To	O
keep	O
M42	O
users	O
in	O
the	O
Pentax	B-Application
system	O
,	O
an	O
M42-K	O
Mount	O
adaptor	O
was	O
offered	O
,	O
enabling	O
them	O
to	O
continue	O
to	O
use	O
their	O
existing	O
lenses	O
,	O
albeit	O
with	O
the	O
loss	O
of	O
automation	O
and	O
needing	O
to	O
accept	O
"	O
stop-down	O
"	O
metering	O
,	O
which	O
causes	O
the	O
viewfinder	O
's	O
image	O
to	O
brighten	O
or	O
darken	O
whenever	O
the	O
aperture	O
's	O
f/stop	O
is	O
changed	O
.	O
</s>
<s>
The	O
K	O
series	O
cameras	O
followed	O
the	O
design	O
ethos	O
of	O
the	O
previous	O
Pentax	B-Algorithm
Spotmatic	I-Algorithm
series	O
cameras	O
,	O
which	O
were	O
large	O
and	O
heavy	O
,	O
although	O
rugged	O
.	O
</s>
<s>
But	O
by	O
1975	O
there	O
was	O
already	O
a	O
general	O
move	O
to	O
smaller	O
35mm	O
cameras	O
,	O
led	O
by	O
the	O
Olympus	B-Algorithm
OM-1	I-Algorithm
,	O
so	O
even	O
as	O
the	O
K	O
series	O
was	O
introduced	O
Pentax	B-Application
were	O
working	O
on	O
a	O
new	O
camera	O
line	O
,	O
the	O
M	O
Series	O
which	O
started	O
to	O
appear	O
in	O
1976	O
.	O
</s>
<s>
All	O
except	O
the	O
K1000	B-Algorithm
therefore	O
had	O
relatively	O
short	O
production	O
lives	O
as	O
the	O
M	O
Series	O
took	O
over	O
the	O
Pentax	B-Application
mid-range	O
.	O
</s>
<s>
The	O
KM	O
,	O
the	O
cheapest	O
of	O
the	O
original	O
three	O
cameras	O
,	O
was	O
almost	O
identical	O
to	O
the	O
Spotmatic	B-Algorithm
F	O
except	O
for	O
the	O
K	B-Algorithm
mount	I-Algorithm
and	O
the	O
top	O
plate	O
cosmetics	O
.	O
</s>
<s>
The	O
K2	O
,	O
the	O
original	O
flagship	O
model	O
,	O
incorporated	O
aperture-priority	B-Algorithm
autoexposure	O
with	O
a	O
fully	O
manually	O
selectable	O
range	O
of	O
shutter	O
speeds	O
from	O
8s	O
to	O
1/1000	O
.	O
</s>
<s>
The	O
only	O
other	O
aperture	B-Algorithm
priority	I-Algorithm
camera	O
Pentax	B-Application
had	O
made	O
up	O
to	O
this	O
point	O
,	O
the	O
ES	O
series	O
,	O
only	O
had	O
manual	O
shutter	O
speeds	O
from	O
1/60	O
upwards	O
.	O
</s>
<s>
The	O
K1000	B-Algorithm
was	O
the	O
KM	O
without	O
the	O
self-timer	O
,	O
depth	O
of	O
field	O
preview	O
and	O
some	O
other	O
facilities	O
,	O
and	O
was	O
aimed	O
at	O
the	O
lower	O
end	O
of	O
the	O
market	O
in	O
which	O
it	O
was	O
very	O
successful	O
and	O
continued	O
in	O
production	O
until	O
1997	O
,	O
helped	O
by	O
the	O
fact	O
that	O
for	O
many	O
years	O
it	O
was	O
the	O
camera	O
usually	O
recommended	O
for	O
students	O
starting	O
photographic	O
or	O
art	O
courses	O
.	O
</s>
<s>
The	O
M	O
series	O
cameras	O
were	O
noted	O
for	O
their	O
compact	O
size	O
,	O
and	O
are	O
among	O
the	O
smallest	O
35mm	O
SLRs	B-Algorithm
ever	O
made	O
,	O
though	O
they	O
are	O
quite	O
heavy	O
when	O
compared	O
to	O
the	O
plastic	O
SLRs	B-Algorithm
of	O
the	O
1990s	O
.	O
</s>
<s>
Except	O
for	O
the	O
MX	B-Algorithm
,	O
all	O
were	O
based	O
on	O
the	O
same	O
basic	O
camera	O
body	O
,	O
and	O
featured	O
aperture-priority	B-Algorithm
exposure	O
automation	O
.	O
</s>
<s>
While	O
superficially	O
resembling	O
the	O
ME	B-Algorithm
,	O
the	O
MX	B-Algorithm
was	O
designed	O
as	O
a	O
manual-only	O
SLR	B-Algorithm
system	O
targeted	O
to	O
the	O
advanced	O
amateur	O
or	O
professional	O
photographer	O
,	O
and	O
had	O
its	O
own	O
set	O
of	O
accessories	O
that	O
were	O
mostly	O
incompatible	O
with	O
the	O
other	O
M	O
series	O
cameras	O
.	O
</s>
<s>
None	O
of	O
the	O
M-series	O
,	O
with	O
the	O
exception	O
of	O
the	O
MX	B-Algorithm
,	O
featured	O
a	O
depth	O
of	O
field	O
preview	O
.	O
</s>
<s>
The	O
ME	B-Algorithm
featured	O
aperture-priority	B-Algorithm
only	O
automation	O
with	O
no	O
manual	O
override	O
.	O
</s>
<s>
The	O
MX	B-Algorithm
was	O
entirely	O
manual	O
and	O
resembled	O
the	O
earlier	O
KX	O
in	O
features	O
.	O
</s>
<s>
The	O
ME	B-Algorithm
Super	I-Algorithm
was	O
an	O
ME	B-Algorithm
with	O
a	O
manual	O
mode	O
.	O
</s>
<s>
The	O
MG	B-Algorithm
,	O
MV	O
,	O
and	O
MV1	O
were	O
even	O
simpler	O
versions	O
of	O
the	O
original	O
ME	B-Algorithm
.	O
</s>
<s>
The	O
ME-F	O
was	O
an	O
early	O
attempt	O
at	O
an	O
autofocus	O
SLR	B-Algorithm
using	O
a	O
special	O
35-70mm	O
zoom	O
with	O
a	O
motor	O
built	O
into	O
the	O
lens	O
.	O
</s>
<s>
The	O
Pentax	B-Algorithm
LX	I-Algorithm
model	O
was	O
a	O
tough	O
,	O
professional-grade	O
competitor	O
to	O
the	O
Nikon	B-Algorithm
F3	I-Algorithm
,	O
the	O
Canon	B-Algorithm
New	I-Algorithm
F-1	I-Algorithm
,	O
Olympus	B-Algorithm
OM-2	I-Algorithm
,	O
and	O
Contax	O
RTS	O
cameras	O
.	O
</s>
<s>
It	O
replaced	O
the	O
K2	O
DMD	O
as	O
the	O
Pentax	B-Application
35mm	O
flagship	O
.	O
</s>
<s>
The	O
LX	O
uses	O
an	O
advanced	O
metering	O
system	O
that	O
also	O
reads	O
the	O
light	O
falling	O
on	O
the	O
film	O
and	O
the	O
first	O
shutter	O
curtain	O
during	O
exposure	O
,	O
the	O
TTL	O
OTF	O
(	O
off	O
the	O
film	O
)	O
feature	O
,	O
a	O
Minolta	O
patent	O
,	O
but	O
utilised	O
in	O
the	O
Olympus	B-Algorithm
OM-2	I-Algorithm
in	O
1975	O
.	O
</s>
<s>
To	O
enable	O
control	O
of	O
the	O
lens	O
aperture	O
by	O
the	O
camera	O
body	O
,	O
it	O
used	O
the	O
new	O
KA-mount	O
,	O
a	O
backward-compatible	O
modification	O
that	O
also	O
allowed	O
the	O
array	O
of	O
standard	O
K-mount	B-Algorithm
lenses	O
to	O
be	O
used	O
in	O
manual	O
and	O
aperture-priority	B-Algorithm
exposure	O
modes	O
.	O
</s>
<s>
The	O
A	O
series	O
were	O
the	O
first	O
cameras	O
from	O
Pentax	B-Application
to	O
use	O
LCD	B-Device
digital	O
displays	O
for	O
exposure	O
information	O
in	O
the	O
viewfinder	O
.	O
</s>
<s>
The	O
super	B-Algorithm
A	I-Algorithm
/	I-Algorithm
super	I-Algorithm
PROGRAM	I-Algorithm
and	O
the	O
program	O
A	O
/	O
program	O
PLUS	O
both	O
used	O
a	O
translucent	O
white	O
window	O
on	O
the	O
front	O
of	O
the	O
pentaprism	O
to	O
provide	O
backlight	O
to	O
the	O
LCD	B-Device
display	I-Device
without	O
having	O
to	O
use	O
the	O
battery	O
for	O
illumination	O
.	O
</s>
<s>
All	O
but	O
the	O
P3/P30	O
also	O
offered	O
Av	B-Algorithm
mode	I-Algorithm
,	O
and	O
the	O
P5/P50	O
offered	O
exposure	O
compensation	O
of	O
±3	O
EV	O
.	O
</s>
<s>
The	O
SFX	O
(	O
called	O
the	O
SF1	O
in	O
the	O
US	O
)	O
was	O
the	O
world	O
's	O
first	O
AF	O
SLR	B-Algorithm
with	O
built-in	O
TTL	O
auto	O
flash	O
,	O
which	O
is	O
retractable	O
.	O
</s>
<s>
Pentax	B-Application
has	O
referred	O
to	O
the	O
built-in	O
flash	O
as	O
"	O
RTF	O
"	O
(	O
Retractable	O
TTL	O
Flash	O
)	O
ever	O
since	O
then	O
.	O
</s>
<s>
Pentax	B-Application
SAFOX	O
I	O
(	O
Sensor	O
Ability	O
Fortifying	O
Optical	O
Correction	O
System	O
)	O
autofocus	O
module	O
was	O
integrated	O
to	O
these	O
series	O
.	O
</s>
<s>
The	O
second	O
generation	O
of	O
autofocus	O
cameras	O
from	O
Pentax	B-Application
.	O
</s>
<s>
This	O
series	O
known	O
as	O
MZ	O
models	O
elsewhere	O
were	O
named	O
ZX	O
models	O
in	O
the	O
USA	O
except	O
MZ-S	B-Algorithm
,	O
the	O
MZ-5	O
being	O
known	O
as	O
the	O
ZX-5	O
in	O
the	O
USA	O
.	O
</s>
<s>
All	O
members	O
of	O
this	O
series	O
are	O
compact	O
autofocus	O
SLRs	B-Algorithm
except	O
the	O
MZ-M	O
.	O
</s>
<s>
The	O
flagship	O
model	O
in	O
this	O
series	O
is	O
the	O
MZ-S	B-Algorithm
which	O
body	O
materials	O
are	O
metal	O
,	O
faster	O
film	O
drive	O
and	O
higher	O
flash	O
sync	O
speed	O
.	O
</s>
<s>
Only	O
MZ-S	B-Algorithm
and	O
MZ-6	O
are	O
compatible	O
with	O
newly	O
introduced	O
P-TTL	O
flash	O
system	O
.	O
</s>
<s>
Models	O
which	O
were	O
also	O
backward	O
compatible	O
with	O
both	O
the	O
KA	O
and	O
K	B-Algorithm
mounts	I-Algorithm
:	O
</s>
<s>
Models	O
which	O
were	O
backward	O
compatible	O
with	O
the	O
KA	O
mount	O
but	O
not	O
the	O
K	B-Algorithm
mount	I-Algorithm
:	O
</s>
<s>
Auto-exposure	O
backward	O
compatible	O
with	O
the	O
KA	O
mount	O
but	O
not	O
the	O
K	B-Algorithm
mount	I-Algorithm
.	O
</s>
<s>
K	B-Algorithm
mount	I-Algorithm
lenses	O
can	O
be	O
used	O
in	O
Manual	O
mode	O
,	O
but	O
the	O
metering	O
needs	O
to	O
be	O
made	O
separately	O
and	O
applied	O
manually	O
,	O
with	O
no	O
indication	O
of	O
aperture	O
in	O
the	O
viewfinder	O
.	O
</s>
<s>
Can	O
also	O
use	O
M42	O
screw-mount	O
lenses	O
in	O
aperture	B-Algorithm
priority	I-Algorithm
(	O
Av	O
)	O
with	O
stop-down	O
metering	O
with	O
the	O
appropriate	O
M42-PK	O
adaptor	O
fitted	O
.	O
</s>
<s>
The	O
Pentax	B-Algorithm
MZ-D	I-Algorithm
,	O
also	O
known	O
by	O
its	O
internal	O
code	O
name	O
of	O
MR-52	O
,	O
was	O
a	O
prototype	O
digital	B-Device
single-lens	I-Device
reflex	I-Device
camera	I-Device
.	O
</s>
<s>
In	O
October	O
2003	O
,	O
Pentax	B-Application
canceled	O
the	O
camera	O
,	O
stating	O
"	O
The	O
cost	O
of	O
manufacturing	O
the	O
prototype	O
SLR	B-Algorithm
6-megapixel	O
digital	O
camera	O
meant	O
it	O
was	O
not	O
a	O
viable	O
product	O
for	O
our	O
target	O
market.	O
"	O
</s>
<s>
In	O
2003	O
Pentax	B-Application
introduced	O
their	O
first	O
Digital	B-Device
SLR	I-Device
under	O
Digital	O
*	O
ist	O
series	O
and	O
released	O
the	O
first	O
flagship	O
model	O
,	O
the	O
Pentax	B-Algorithm
*	I-Algorithm
ist	I-Algorithm
D	I-Algorithm
which	O
uses	O
a	O
Sony	O
6	O
megapixel	O
CCD	B-Algorithm
.	O
</s>
<s>
Since	O
2003	O
,	O
the	O
*	O
ist	O
D	O
is	O
the	O
only	O
digital	B-Device
SLR	I-Device
that	O
can	O
control	O
HS	O
wireless	O
P-TTL	O
from	O
its	O
pop-up	O
flash	O
and	O
has	O
many	O
advanced	O
features	O
for	O
professional	O
applications	O
.	O
</s>
<s>
In	O
2004	O
Pentax	B-Application
released	O
the	O
second	O
member	O
in	O
the	O
digital	O
*	O
ist	O
line	O
,	O
the	O
Pentax	B-Algorithm
*	I-Algorithm
ist	I-Algorithm
DS	I-Algorithm
which	O
is	O
the	O
first	O
real	O
consumer	O
model	O
(	O
retailing	O
under	O
US$	O
1,000	O
)	O
.	O
</s>
<s>
What	O
set	O
Pentax	B-Application
D	O
and	O
DS	O
DSLRs	B-Device
apart	O
from	O
the	O
competition	O
was	O
the	O
clarity	O
and	O
high	O
magnification	O
provided	O
by	O
their	O
pentaprism	O
viewfinders	O
,	O
a	O
very	O
useful	O
feature	O
considering	O
the	O
support	O
for	O
legacy	O
manual	O
focus	O
lenses	O
.	O
</s>
<s>
In	O
2005	O
Pentax	B-Application
released	O
the	O
Pentax	B-Algorithm
*	I-Algorithm
ist	I-Algorithm
DL	I-Algorithm
,	O
a	O
model	O
with	O
fewer	O
features	O
than	O
the	O
D	O
and	O
DS	O
with	O
a	O
lower	O
price	O
.	O
</s>
<s>
All	O
Pentax	B-Application
's	O
digital	B-Device
SLRs	I-Device
are	O
compatible	O
with	O
K-mount	B-Algorithm
lenses	O
,	O
and	O
M42	O
(	O
42mm	O
screw	O
mount	O
)	O
lenses	O
(	O
with	O
adaptor	O
)	O
.	O
</s>
<s>
Due	O
to	O
the	O
smaller	O
size	O
of	O
the	O
CCD	B-Algorithm
,	O
lenses	O
have	O
an	O
effective	O
field	O
of	O
view	O
of	O
1.5	O
×times	O
the	O
same	O
lens	O
in	O
35mm	O
format	O
.	O
</s>
<s>
To	O
address	O
this	O
"	O
crop	O
factor	O
,	O
"	O
Pentax	B-Application
created	O
a	O
new	O
series	O
of	O
lenses	O
that	O
were	O
designed	O
only	O
to	O
cover	O
the	O
smaller	O
sensor	O
.	O
</s>
<s>
These	O
are	O
the	O
DA	O
series	O
for	O
their	O
digital	B-Device
SLRs	I-Device
,	O
which	O
still	O
feature	O
the	O
K-mount	B-Algorithm
but	O
have	O
a	O
smaller	O
back-focus	O
element	O
designed	O
specifically	O
for	O
use	O
with	O
the	O
Digital	B-Device
SLR	I-Device
lineup	O
.	O
</s>
<s>
The	O
later	O
D-FA	O
lens	O
series	O
re-introduces	O
a	O
mechanical	O
aperture	O
ring	O
in	O
some	O
lenses	O
and	O
these	O
are	O
fully	O
compatible	O
with	O
both	O
film	O
and	O
digital	B-Device
SLRs	I-Device
.	O
</s>
<s>
In	O
May	O
2006	O
,	O
Pentax	B-Application
announced	O
a	O
new	O
line	O
of	O
Digital	B-Device
SLR	I-Device
cameras	I-Device
to	O
replace	O
Digital	O
*	O
ist	O
series	O
.	O
</s>
<s>
The	O
K100D	B-Algorithm
and	O
K110D	B-Algorithm
replaced	O
*	O
ist	O
DL2	O
and	O
DS2	O
,	O
while	O
incorporating	O
in-body	O
shake	O
reduction	O
in	O
the	O
K100D	B-Algorithm
model	O
.	O
</s>
<s>
The	O
Pentax	B-Algorithm
K10D	I-Algorithm
,	O
a	O
new	O
flagship	O
model	O
in	O
Digital	O
K	O
series	O
replaced	O
*	O
ist	O
D	O
,	O
adopted	O
Sony	O
10-megapixel	O
CCD	B-Algorithm
sensor	I-Algorithm
and	O
weather-sealing	O
construction	O
,	O
was	O
announced	O
on	O
14	O
September	O
2006	O
.	O
</s>
<s>
The	O
K10D	B-Algorithm
featured	O
a	O
pentaprism	O
viewfinder	O
(	O
instead	O
of	O
the	O
slightly	O
dimmer	O
pentamirror	O
on	O
some	O
previous	O
models	O
)	O
,	O
full	O
programmed	O
,	O
aperture	O
and	O
shutter	O
priority	O
modes	O
,	O
and	O
a	O
new	O
Sensitivity-priority	O
mode	O
where	O
the	O
rear	O
dial	O
adjusts	O
light	O
sensitivity	O
and	O
the	O
camera	O
adjusts	O
shutter	O
speed	O
and	O
aperture	O
to	O
maintain	O
correct	O
exposure	O
.	O
</s>
<s>
Power	O
contacts	O
on	O
the	O
lens	O
mount	O
were	O
introduced	O
to	O
enable	O
Pentax	B-Application
's	O
SDM	O
(	O
Supersonic	O
Drive	O
Motor	O
)	O
for	O
silent	O
focusing	O
.	O
</s>
<s>
The	O
power	O
contacts	O
also	O
provide	O
the	O
power	O
zoom	O
function	O
in	O
some	O
FA	O
lens	O
that	O
Pentax	B-Application
introduced	O
in	O
the	O
1990s	O
.	O
</s>
<s>
In	O
addition	O
,	O
the	O
K10D	B-Algorithm
could	O
write	O
JPEGs	O
and	O
two	O
versions	O
of	O
RAW	B-Application
files	I-Application
(	O
PEF	O
,	O
and	O
the	O
Adobe	O
specification	O
DNG	B-Application
)	O
.	O
</s>
<s>
The	O
K100D	B-Algorithm
Super	I-Algorithm
was	O
a	O
slight	O
upgrade	O
to	O
the	O
K100D	B-Algorithm
announced	O
in	O
June	O
2007	O
.	O
</s>
<s>
The	O
upgrade	O
included	O
some	O
features	O
from	O
the	O
K10D	B-Algorithm
,	O
such	O
as	O
an	O
improved	O
shake	O
reduction	O
(	O
SR	O
)	O
system	O
,	O
a	O
dust	O
removal	O
system	O
,	O
and	O
power	O
contacts	O
for	O
SDM	O
lenses	O
,	O
but	O
which	O
could	O
not	O
enable	O
the	O
power	O
zoom	O
function	O
as	O
the	O
K10D	B-Algorithm
.	O
</s>
<s>
On	O
January	O
23	O
,	O
2008	O
,	O
Pentax	B-Application
announced	O
the	O
K20D	B-Algorithm
and	O
K200D	B-Algorithm
,	O
which	O
replaced	O
the	O
K10D	B-Algorithm
and	O
K100D	B-Algorithm
series	O
respectively	O
.	O
</s>
<s>
The	O
K20D	B-Algorithm
featured	O
a	O
Samsung	B-Application
14.6	O
megapixel	O
CMOS	B-Device
APS-C	B-Algorithm
sized	O
sensor	O
,	O
a	O
special	O
21frame/s	O
burst	O
mode	O
,	O
live	B-Device
preview	I-Device
on	O
the	O
LCD	B-Device
display	I-Device
,	O
and	O
an	O
increased	O
sensitivity	O
range	O
extending	O
to	O
ISO	O
3200	O
.	O
</s>
<s>
The	O
K200D	B-Algorithm
adopted	O
the	O
10megapixel	O
sensor	O
and	O
weather	O
sealing	O
of	O
the	O
K10D	B-Algorithm
,	O
among	O
other	O
improvements	O
,	O
while	O
retaining	O
the	O
smaller	O
body	O
size	O
of	O
the	O
K100D	B-Algorithm
Super	I-Algorithm
.	O
</s>
<s>
The	O
K-m	B-Algorithm
/	I-Algorithm
K2000	I-Algorithm
for	I-Algorithm
US	I-Algorithm
was	O
announced	O
on	O
September	O
22	O
,	O
2008	O
at	O
the	O
2008	O
photokina	O
trade	O
show	O
along	O
with	O
the	O
DA-L	O
series	O
of	O
lightweight	O
,	O
inexpensive	O
lenses	O
.	O
</s>
<s>
On	O
May	O
20	O
,	O
2009	O
,	O
Pentax	B-Application
announced	O
the	O
K-7	B-Algorithm
as	O
a	O
replacement	O
for	O
the	O
K20D	B-Algorithm
.	O
</s>
<s>
It	O
introduced	O
an	O
updated	O
version	O
of	O
the	O
Samsung	B-Application
CMOS	B-Device
sensor	O
,	O
but	O
with	O
an	O
entirely	O
new	O
compact	O
design	O
.	O
</s>
<s>
The	O
K-7	B-Algorithm
was	O
available	O
from	O
July	O
2009	O
.	O
</s>
<s>
In	O
September	O
2009	O
the	O
K-x	B-Device
,	O
was	O
introduced	O
to	O
replace	O
the	O
entry	O
level	O
K-m	B-Algorithm
/	O
K2000	O
(	O
US	O
)	O
.	O
</s>
<s>
In	O
September	O
2010	O
Pentax	B-Application
announced	O
the	O
K-r	B-Algorithm
,	O
a	O
6	O
frames	O
per	O
second	O
12.4	O
megapixel	O
camera	O
and	O
the	O
K-5	B-Algorithm
,	O
a	O
7	O
frames	O
per	O
second	O
16.3	O
megapixel	O
camera	O
.	O
</s>
<s>
In	O
February	O
2012	O
information	O
about	O
the	O
Pentax	B-Algorithm
K-01	I-Algorithm
Mirrorless	B-Device
camera	I-Device
was	O
released	O
.	O
</s>
<s>
It	O
still	O
uses	O
the	O
standard	O
K	B-Algorithm
mount	I-Algorithm
but	O
lacks	O
an	O
optical	O
reflex	O
viewfinder	O
.	O
</s>
<s>
The	O
K-01	B-Algorithm
quickly	O
became	O
one	O
of	O
the	O
most	O
controversial	O
Pentax	B-Application
offerings	O
,	O
with	O
criticism	O
focusing	O
on	O
the	O
innovative	O
Marc	O
Newson	O
design	O
,	O
which	O
many	O
considered	O
made	O
the	O
camera	O
uncomfortable	O
to	O
hold	O
,	O
with	O
poorly-placed	O
controls	O
,	O
while	O
acknowledging	O
its	O
strong	O
image	O
quality	O
and	O
low-light	O
/	O
high	O
ISO	O
performance	O
.	O
</s>
<s>
Pentax	B-Application
announced	O
a	O
new	O
mid-level	O
DSLR	B-Device
,	O
the	O
K-30	B-Algorithm
,	O
in	O
May	O
2012	O
.	O
</s>
<s>
It	O
has	O
the	O
same	O
APS-C	B-Algorithm
sensor	O
and	O
processor	O
as	O
the	O
K-01	B-Algorithm
,	O
and	O
is	O
fully	O
weather-sealed	O
.	O
</s>
<s>
In	O
September	O
2012	O
,	O
Pentax	B-Application
announced	O
the	O
successor	O
to	O
the	O
K-5	B-Algorithm
,	O
the	O
K-5	B-Algorithm
II	I-Algorithm
.	O
</s>
<s>
It	O
has	O
the	O
same	O
APS-C	B-Algorithm
sensor	O
as	O
the	O
K-5	B-Algorithm
,	O
but	O
has	O
an	O
improved	O
autofocus	O
sensor	O
and	O
a	O
redesigned	O
rear	O
LCD	B-Device
with	O
no	O
air	O
gap	O
.	O
</s>
<s>
A	O
version	O
of	O
the	O
camera	O
without	O
an	O
anti-aliasing	O
filter	O
would	O
be	O
sold	O
as	O
the	O
K-5	B-Algorithm
IIs	I-Algorithm
.	O
</s>
<s>
In	O
June	O
2013	O
Pentax	B-Application
announced	O
the	O
successors	O
to	O
the	O
K-30	B-Algorithm
,	O
the	O
K-50	B-Algorithm
and	O
K-500	O
.	O
</s>
<s>
Both	O
are	O
mid-level	O
DSLRs	B-Device
,	O
the	O
K-500	O
being	O
a	O
stripped-down	O
version	O
of	O
the	O
K-50	B-Algorithm
,	O
having	O
no	O
weather	O
seals	O
and	O
less-advanced	O
electronics	O
.	O
</s>
<s>
Pentax	B-Application
K-500	O
uses	O
4	O
AA	O
batteries	O
(	O
rechargeable	O
Lithium	O
battery	O
is	O
optional	O
)	O
,	O
while	O
Pentax	B-Algorithm
K-50	I-Algorithm
uses	O
rechargeable	O
Lithium	O
battery	O
.	O
</s>
<s>
In	O
October	O
2013	O
Pentax	B-Application
launched	O
the	O
successor	O
to	O
the	O
K-5ii	O
and	O
K-5iis	O
,	O
the	O
Pentax	B-Algorithm
K-3	I-Algorithm
.	O
</s>
<s>
The	O
K-3	O
is	O
the	O
first	O
DSLR	B-Device
to	O
use	O
its	O
shake	O
reduction	O
system	O
to	O
function	O
as	O
an	O
anti-aliasing	O
filter	O
.	O
</s>
<s>
It	O
has	O
a	O
24.71	O
megapixel	O
sensor	O
and	O
other	O
improvements	O
over	O
the	O
K-5	B-Algorithm
but	O
maintains	O
the	O
rugged	O
stainless	O
steel	O
frame	O
and	O
magnesium	O
alloy	O
body	O
construction	O
,	O
complete	O
with	O
92	O
body	O
seals	O
thereby	O
rendering	O
the	O
camera	O
cold-proof	O
and	O
water	O
resistant	O
.	O
</s>
<s>
In	O
March	O
2010	O
Pentax	B-Application
announced	O
its	O
first	O
medium	O
format	O
digital	O
camera	O
,	O
the	O
Pentax	B-Algorithm
645D	I-Algorithm
.	O
</s>
<s>
It	O
uses	O
a	O
40	O
megapixels	O
,	O
44mm	O
×	O
33mm	O
CCD	B-Algorithm
sensor	I-Algorithm
.	O
</s>
<s>
The	O
51.4	O
megapixel	O
CMOS	B-Device
sensor	O
645Z	B-Algorithm
was	O
announced	O
in	O
February	O
2014	O
at	O
the	O
CP+	O
2014	O
Camera	O
and	O
Imaging	O
Show	O
.	O
</s>
<s>
In	O
June	O
2011	O
Pentax	B-Application
announced	O
the	O
'	O
Pentax	B-Algorithm
Q	I-Algorithm
 '	O
mirrorless	B-Device
interchangeable	I-Device
lens	I-Device
camera	I-Device
and	O
the	O
'	O
Q-mount	O
'	O
lens	O
system	O
.	O
</s>
<s>
It	O
has	O
a	O
small	O
,	O
1/2.3inch	O
12.4	O
megapixel	O
LED	O
Backlit	O
CMOS	B-Device
sensor	O
.	O
</s>
<s>
The	O
Optio	B-Device
line	I-Device
is	O
a	O
series	O
of	O
consumer	O
digital	O
cameras	O
.	O
</s>
<s>
In	O
early	O
2015	O
,	O
Ricoh	O
announced	O
development	O
of	O
a	O
Pentax	B-Application
full-frame	B-Algorithm
DSLR	I-Algorithm
for	O
release	O
later	O
in	O
the	O
year	O
,	O
and	O
at	O
the	O
CP+	O
show	O
in	O
Yokohama	O
Japan	O
,	O
a	O
mockup	O
was	O
displayed	O
that	O
suggested	O
the	O
camera	O
's	O
potential	O
specifications	O
,	O
including	O
:	O
an	O
IR	O
port	O
for	O
remote	O
release	O
,	O
an	O
anti-aliasing	O
filter	O
simulation	O
mode	O
,	O
and	O
an	O
articulating	O
rear	O
LCD	B-Device
.	O
</s>
<s>
On	O
February	O
17	O
,	O
2016	O
Ricoh	O
unveiled	O
the	O
Pentax	B-Algorithm
K-1	I-Algorithm
full-frame	B-Algorithm
DSLR	I-Algorithm
with	O
36MP	O
sensor	O
.	O
</s>
<s>
Pentax	B-Application
is	O
one	O
of	O
the	O
few	O
camera	O
manufacturers	O
still	O
producing	O
medium	O
format	O
cameras	O
up	O
to	O
1999	O
.	O
</s>
<s>
There	O
are	O
two	O
offerings	O
,	O
one	O
in	O
the	O
6×7	O
format	O
—	O
the	O
Pentax	B-Algorithm
67	I-Algorithm
II	I-Algorithm
,	O
and	O
one	O
in	O
the	O
6×	O
4.5	O
format	O
—	O
Pentax	B-Application
645NII	O
.	O
</s>
<s>
These	O
cameras	O
build	O
on	O
the	O
Pentax	B-Application
SLR	B-Algorithm
design	O
experience	O
.	O
</s>
<s>
The	O
shape	O
of	O
the	O
Pentax	B-Algorithm
67	I-Algorithm
is	O
broadly	O
similar	O
to	O
a	O
35mm	O
SLR	B-Algorithm
camera	I-Algorithm
.	O
</s>
<s>
By	O
contrast	O
,	O
the	O
Pentax	B-Algorithm
645	I-Algorithm
resembles	O
other	O
medium-format	O
cameras	O
by	O
makers	O
such	O
as	O
Mamiya	O
and	O
Bronica	B-Algorithm
,	O
which	O
tend	O
to	O
be	O
cube-shaped	O
.	O
</s>
<s>
Previous	O
models	O
include	O
the	O
Pentax	B-Algorithm
645	I-Algorithm
and	O
645N	O
,	O
and	O
Asahi	B-Algorithm
Pentax	I-Algorithm
6x7	I-Algorithm
,	O
Pentax	B-Algorithm
6x7	I-Algorithm
and	O
Pentax	B-Algorithm
67	I-Algorithm
.	O
</s>
<s>
Another	O
interesting	O
product	O
was	O
the	O
tiny	O
Auto	B-Algorithm
110	I-Algorithm
reflex	O
system	O
,	O
based	O
on	O
the	O
110	O
pocket-instamatic	O
film	O
format	O
.	O
</s>
