All Pentax digital SLR bodies are compatible with older Pentax film
lenses (FA, F and A mounts) as well as newer lenses (DA and DA*
mounts). The Pentax K10D is the cheapest weather-sealed digital SLR
body on the market. Pentax offers a different approach to image
stabilization than market leaders Canon and Nikon. The Pentax DSLR
bodies electronically shake their sensors to compensate for camera
shake, rather than adding image stabilization to specific lenses. The
Pentax system is not as effective as in-lens image stabilization and
it isn't very effective for long telephoto lenses, but it does work
with all lenses, including old designs from the film years.
This article covers every current Pentax product and some good
All Pentax digital
SLR bodies incorporate an APS-C sized
sensor. The sensor size is 23.5x15.7mm, smaller than the standard
35mm film frame (36x24mm). The small or "crop" sensor on the Pentax
DSLR bodies means that lenses don't function the way that they do on a
film camera. Multiply focal lengths by 1.5x to calculate the "35mm
equivalent". A 50mm lens that would be "normal" for a film camera,
for example, will function as a good portrait lens on a Pentax digital
body. This magnification will be welcomed by wildlife photographers
and cursed by owners of high-quality high-speed wide-angle lenses (a
dramatic 21mm gives a boring 31mm equivalent perspective).
"DR" is the Pentax-original Dust Removal system, which helps keep the
CCD surface dust-free.
"DA" refers to the series of lenses engineered exclusively for digital
cameras. All DA-series lenses feature a responsive "Quick-Shift Focus
System" that allows photographers to instantly switch the focus mode
from auto to manual with a slight twist of the focus ring.
"DA*" refers to the series of lenses designed for exclusive use with
Pentax digital SLR cameras. The DA* lenses feature tightly sealed,
weather-resistant and dust-resistant construction for use in rain or
"FA" specifies the autofocus lens series compatible with both film and
digital SLR bodies.
"AL" stands for "aspherical lens."
"FA-J" designates a line of cheaper autofocus lenses
without an aperture ring, compatible with both film and
digital SLR bodies.
"A" designates a line of old manual focus lenses.
"SP" refers to a Super Protect lens coating applied on all Pentax
lenses, where the surface is coated with a special fluorine compound
to repel dust, water and grease, making it easy to wipe off
fingerprints and cosmetics.
"ED" is "extra-low dispersion" glass, a more expensive and higher
quality glass that reduces chromatic aberration, in which light of
different colors takes different paths through the lens, which would
result in a dot of white light being fuzzed up by the time it reaches
the film or sensor.
"IF" is internal focus, meaning that the lens does not change physical
length as you focus on subjects that are closer or farther away.
"SDM" is "Supersonic Drive Motor", the Pentax equivalent to Canon's
in-lens ultrasonic motor. SDM makes autofocus faster and facilitates
simultaneous use of manual and autofocus, which Canon calls "full-time
manual focus" and what Pentax calls "quick-shift focus system".
A normal lens is light in weight and approximates the
perspective of the human eye. Normal lenses generally have large
maximum apertures, indicated by small f-numbers such as f/1.4 or
f/1.8, and thereby gather much more light than zoom lenses. It may be
possible to take a photo with a normal lens in light only 1/8th or
1/16th as bright as would be required for the same photo with a
consumer-priced zoom lens. Also, the viewfinder will be brighter and
therefore easier to use in dim light, due to the fact that the large
maximum aperture stays open for viewing and stops down to whatever
aperture you have set just before taking the picture.
A wide-to-tele zoom is what you get as a standard "kit" lens with a
consumer-grade digital SLR body. The range goes from moderately wide
normal to moderately telephoto. They are good when you are too busy
to change lenses, e.g., at a wedding reception. A 16mm focal length at
the wide end
will capture a table of guests; the 45-55mm long
end is good for a flattering portrait. The main weakness of these
is that the cheaper ones have a very small maximum aperture, e.g., f/4
or f/5.6, and can only be used in bright light, on a tripod, or with a
blast of on-camera flash that gives everyone a moon face.
Pentax DA* 50-135mm f/2.8 ED IF SDM, (buy from Amazon), (effective 75-202.5mm), 685g,
the function of a standard full-frame 70-200/2.8 lenses at less than
half the weight (Canon's 70-200/2.8 is a shoulder-breaking 1470g);
Canon and Nikon should be ashamed of themselves for not making a lens
like this for their small sensor bodies.
prime lens offers excellent image quality at long focal lengths
due to a large maximum aperture and magnification of the subject, and
can be handheld in low-light situations. When comparing a telephoto
prime to a normal-to-telephoto zoom, although zoom lenses cover wide
ranges, they usually have a smaller maximum aperture on the long end.
Keep in mind that on a small sensor, the effective
focal length of a telephoto prime is multiplied by 1.5.
Pentax FA 77mm f/1.8 Limited, (buy from Amazon), (effective 115mm), specifically
designed for portrait photography on old film SLRs; the wide maximum
aperture enables the photographer to choose a very narrow depth of
field, throwing distracting backgrounds out of focus.
Note that Pentax does not make any teleconverters for its autofocus
Macro lenses let you
photograph physically small objects. The longer the focal length of
the macro lens, the more space you can put between the camera and the
subject. Extra working distance is helpful in lighting scenes or
keeping insects calm. A macro lens that goes down to "1:1" can be
used to take a frame-filling photo of something that is roughly
23x16mm in size, the dimensions of the APS-C sized sensor on a Pentax
digital body. The macro lenses below can be used for ordinary
photographic projects as well, i.e., they will focus out to infinity
Straight ahead on-camera flash blasts the subject with an unflattering
light. Pictures will look just as you saw them with your
eyes... assuming you are in the habit of walking around with a
spotlight on top of your head. The built-in flash of Pentax bodies
only points forward and is therefore mostly useful outdoors for
filling in harsh shadows. The accessory flashes below can be titled
up towards the ceiling or used at a distance from the camera for more
For a camera body and one lens, the average professional photographer
would not use a case at all. To hold a camera system, it is
best to visit a nearby professional camera shop and see how your gear
fits in various bags. See the photo.net
camera bag article for some ideas.