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VANTAGE CC620DC COLOUR CAMERA
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WHAT OUR EXPERTS SAY...
Flexibility is one of the most important, yet
most frequently overlooked criteria when specifying video surveillance cameras.
Conditions can and do change, often quite rapidly. A camera and lens that may
have been ideally suited to a particular site or situation when it was
installed, may suddenly be rendered inadequate following building work, changes
to lighting conditions, imaging requirements or patterns of use.
Change is something the Vantage CC620DC
colour camera can take in its stride. It’s a highly versatile design that’s quick
and easy to set up, or re-configure, with the kind of performance that will
enable it to keep up with improvements elsewhere in a system.
From the outside it looks reasonably
conventional. The high-performance 0.5-inch CCD image sensor and electronics
are housed inside a gently rounded rectangular, cream-coloured case, measuring 140
x 62 x 73mm. All panels are made from a heavy gauge durable cast alloy, they’re
close fitting with no gaps, though the case is not actually weatherproof. The
front cap has a threaded collar for C or CS mount lenses; back focus and C/CS
adjustment is affected using a brass thumbwheel protruding through a slot on the
left side. Two 1/4-in mounting threads are moulded into the top and bottom
panels. The rear panel has three sockets: BNC and mini DIN connectors for
composite and Y/C video outputs, and a square four-pin socket for an optional auto
iris lens connection. The camera is powered by a 12 volt DC supply, connected
to the camera by a set of screw terminals. Two other variants are also
available, with 24 VAC or 230 VAC power supplies.
Inside the 12 VDC model we’ve been looking at
there are four glass-fibre PCBs, densely populated with surface mount
components. They’re grouped on the front, side and top of the case, leaving plenty of room for the power supply board on the
mains version. The quality of construction is very good indeed. The PCBs are held
in position by moulded alloy pillars. The back-focus adjustment deserves a
special pat on the back. For a mechanism that’s likely to be used only once or
twice during its life time, it is distinctly over-engineered. The PCB containing
the image sensor chip slides smoothly back and forth on chrome-plated pillars. The
action is taught, yet easy to adjust, and once set, can be locked in place using
the Allen key provided.
The only slightly unusual external feature about
the design is a sliding plastic cover on the left side of the body. This opens
to reveal a control panel containing a four-way miniature DIP switch,
three-position slide switch, 10-way rotary switch and four preset
potentiometers.
OPERATION
The DIP switch is used to switch the
backlight on and off, auto/manual white balance, AGC on/off and internal or
line/lock synchronisation. The slide switch sets auto iris mode (off, DC or
video controlled), whilst the rotary switch controls the manual electronic
shutter speed (1/50th to 1/1200th sec), auto shutter mode (1/50th to
1/100,000th sec) and a fixed speed of 1/50th for when the camera is set for
auto iris operation. The four preset
pots are used to adjust red and blue gain, for fine-tuning white balance; the
level and ALC adjustment are used for setting up auto-iris lenses.
At this point its worth saying that the
instructions are a tad brief. Actually that’s an understatement, they’re printed
on a single sheet of a sheet of A4 paper. To be fair all of the information an
experienced installer is likely to need is there but some of the set-up routines
are dealt with in a not much more than a single line of text. All routine adjustments
are easy to carry out -- assuming the sliding hatch is easily accessible when
the camera is in situ -- and under
normal circumstances it should be up and running in no more than a few minutes.
PERFORMANCE
The stated resolution of 460 lines is not too
far off the mark, under normal test conditions our sample managed 430 lines
without any difficulty on a Y/C feed. Resolution on a composite video
connection was only slightly lower, at just under 420 lines. However, one of the most impressive features
of this camera has to be the very low levels of noise. The picture is exceptionally
clean in natural light. Low frequency response is good, with no significant smearing
on sharp light-dark transitions, edges are very well defined and there’s little
or no dot-crawl. Grain increases as light levels decrease, though with a
minimum sensitivity of just 1.5 lux (F1.4), it is still producing a useable
image, when a lot of other colour cameras have given up.
Colour fidelity is also a cut above the norm,
accuracy is difficult to fault in natural light. Tungsten light produces a very
slight orange caste and tube lighting give the characteristic yellow tinge,
though both types of colour imbalance can be easily compensated for, using the
manual colour controls. The auto exposure systems cope very well with gradual
changes in light levels. The wide-range electronic shutter in particular works
well enough to make auto iris lenses virtually redundant in all but the most
critical applications.
Our standard intermittency test -- a series
of sharp knocks with the handle of a screwdriver -- produced no picture
disturbance.
OVERALL ASSESSMENT
We normally expect to uncover the odd flaw or
operational niggle -- the perfect camera has yet to be built -- but apart from
the brevity of the instructions, the Vantage CC620DC passed all of our tests
with flying colours. Picture performance is excellent, it is very well built
and there’s every reason to suppose it will give years of useful service.
PRODUCT ASSESSMENT
Design and design features ****
Circuitry and components ****
Ease of installation and wiring *****
Range and variety of functions ****
Accompanying instructions ****
Technical advice and backup ****
Value for money ??
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Ó R.Maybury 1997 2209
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