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CANON TF2812D, TF0412D & TF0813D CAMERAS
STANDFIRST
There are a lot of unfamiliar names floating around the CCTV
industry these days and it pays to be careful when specifying critical
components. When it comes to camera lenses few -- if any -- brands can match
the reputation of Canon.
COPY
It's easy to overlook the fact that a CCTV camera is only as
good as the lens attached to it. Cameras naturally attract a lot of attention
because they're stuffed full of the latest microchip wizardry and do so many
clever things. Lenses on the other hand appear to be relatively low-tech items,
there's little to go wrong and even less to get excited about but choosing the
right one is just as important as selecting the right camera; more so in some
circumstances.
Lens selection is made more difficult by the seemingly vast
array of types available, bearing numerous different brand names. Some of them
you will undoubtedly know and respect, others come and go, and a few are best
forgotten… Canon obviously falls into the former category. Their optical
expertise stretches far and wide, from humble snap cameras to powerful high
definition studio camera lenses, and everything in between, encompassing photographic,
surveillance, commercial, industrial, medical and scientific imaging fields, to
name just a few.
That's by way of a preamble to introduce and put into
context Canon CCTV lenses. There really is a lens to suit just about every
camera, configuration and application. The current catalogue lists almost 70
basic types. It would be impossible to cover them all, however, we've been looking
at (and through…) a small but representative sample, that illustrates the scope
and performance of Canon's product range.
The five lenses fall into three distinct categories: compact
fixed focal length models with DC controlled auto irises, a vari-focal type, again
with DC auto iris, and lastly, what Canon describes as an 'Economical' motorised
zoom lens.
Our group test included three fixed focal length lenses, they
are TF2812D, TF0412D and TF0813D, designed to be used with small lightweight
cameras with 1/3-inch CCD image sensors. They weigh in at around 40 g apiece, have
CD type mounting collars and are fitted with a 26cm cable, terminated in a
standard 4-pin auto iris plug. The only other external detail is a lockable ring-type
rear focus adjustment and a small bulge that houses the iris actuator. The
principle differences concern the focal lengths which are 2.8, 4 and 8mm respectively;
the maximum apertures are F1.2 (TF2812D & TF0412D) and F1.3 for the
TF0813D.
The outer cases are made from tough ABS plastic and the
multi-coated lenses are well protected against physical shock. The quality of
construction and finish is generally good; inside the case the wiring is neatly
laid out and the actuator mechanism looks as though it should enjoy a long and
healthy life. The irises are two-leaf types with a fast, smooth and progressive
action. The seal between the case and end caps wasn't very tight. You could actually
see light through the join on one of our samples, so you can take it as read
they're not suitable for use outdoors -- without a housing -- or in a dusty
environment. Fitting and adjustment are straightforward; the camera mount will
rotate when tightened, to allow the lens to be orientated to the most suitable
attitude.
A simple tele-wide adjustment is the key feature on TV351D
Vari-Focal lens. Again it is designed to be used with cameras having a 1/3-inch
image sensor; the focal length in this case is 3.5 to 8mm with an aperture of
F1.4. The housing is slightly larger than the previous three and tips the
scales at 70 g so it is better suited to medium sized cameras, with a CS
mounting collar. The DC auto iris cable is the same length as the other three
and fitted with a 4-pin plug. The manual focus adjusting collar is on the front
of the lens, behind that is the tele-wide ring. The mounting collar rotates so
the lens can be aligned as required. The case is very well put together and if
anything looks and feels even more robust than the fixed focal length models.
Finally, the T10X6.5RG CS. This is a substantial motorised
zoom lens, designed to be used with medium and large-scale cameras fitted with
1/3-inch CCDs. It is a big lens with wide operating range having a 6.5 - 65mm
focal length and an aperture of F1.4 - 256. The auto iris is a DC controlled
type and the focus adjustment is motorised as well. It is housed inside a
cream-coloured ABS case with the iris zoom and focus control cable emerging
from the top, this is 50 cm long and is terminated in a 4-pin DIN plug with a
retaining collar. An unwired female 4-pin DIN is included with the camera. On
the underside of the lens there's a standard 1/4-inch UNC threaded mounting collar
to take the weight of the lens (450 g), when it is used in a housing. There are
no external adjustments or fittings. In common with its stablemates fitting is
very simple to fit and the mounting collar rotates freely so the lens can be turned.
The instructions are not especially helpful. They're generic
-- applicable to a wide range of similar models -- and imply that there are a
number of user adjustments, when in fact there aren't any. Moreover there is a
mysterious blanked off hole, and what appears to be a standard 4-pin auto-iris socket,
neither of which are explained. It would also have been helpful to include some
mounting information or advice, as this is quite a weighty object. On the plus
side the lens is very quiet and the focus and zoom actions are both smooth.
SUMMARY
The one thing we haven't covered so far is the optics. In keeping
with the tradition of leaving the best things until last we are happy to report
that all five lenses turned in an excellent performance. In all cases the image
was pin-sharp, up to the edges of the picture. We tried the lenses in a range of typical and unfavourable
lighting conditions and there were no significant aberrations or distortions. Internal reflections are occasionally apparent
but this only happens over a very narrow band of lens/light source angles and
can be easily compensated for with a relatively minor adjustment to the camera
position.
We have very some minor misgivings about the cases on the small
fixed focal length models, and the instruction leaflets are a bit brief.
Nevertheless the Canon name inspires a great deal of confidence in installers
and end-users but most important of all, all five lenses look, feel and perform
like quality items.
PRODUCT SPECIFICATION
TF2812D
Focal length 2.8mm
Aperture F1.2 - 180
Iris type DC auto
Focus manual
Angle of view 81.2 degrees
Weight 40 g
Mount/plug CS/Sq 4-pin
TF0412D
Focal length 4mm
Aperture F1.2 - 200
Iris type DC auto
Focus manual
Angle of view 61.9 degrees
Weight 40 g
Mount/plug CS/Sq 4-pin
TF0813D
Focal length 8mm
Aperture F1.3 - 256
Iris type DC auto
Focus manual
Angle of view 33.4
Weight 40 g
Mount/plug CS/Sq 4-pin
TV3514D
Focal length 3.5 - 8mm
Aperture F1.4 - 256
Iris type DC auto
Focus manual
Angle of view 68.9 - 33.4 degrees
Weight 70 g
Mount/plug CS/Sq 4-pin
T10X6.5RG CS
Focal length 6.5 - 65mm
Aperture F1.4 - 256
Iris type DC auto
Focus motorised
Zoom 10x motorised
Angle of view 40.5 - 4.2 degrees
Weight 450 g
Mount/plug CS/4-pin DIN
PSI RATINGS (all samples)
Product 9
Product design 9
Build quality 8
Ruggedness 8
Performance 9
Operation 9
General functions 9
Ease of use 9
Instructions 6
Manuf. support 8
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R. Maybury 1998 1011
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