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VISTA
VPM3130 CCTV CAMERA
The Vista VPM3130 mono CCTV camera has a reassuringly solid feel about
it. That’s mainly due to the cast alloy casing and metal chassis, a hark back
to an earlier age, though this one is bang up to date is just about every other
respect, and an unusually versatile design with applications extending well
beyond video security and surveillance.
The 3130 is based around a 0.3-inch CCD imaging chip; it’s available in
a variety of configurations, this particular one has its own on-board mains
power supply, and a near universal fitting for almost any 1/3, 1/2, 2/3 or
1-inch format C or CS mount lens, with manual,
automatic or direct-drive iris. The two-part case is an unusual design,
apart from contributing to almost fifty percent of the all-up weight of just
over 1kg, the curvy shape makes a refreshing change to the succession of bland
boxes we’ve become used to. It has two hinged side panels, one side is purely
cosmetic, but the other one opens to reveal two DIP switches, one of which
controls the high-speed shutter, the other sets various exposure options, plus
gamma correction level and secondary functions, which we’ll come to in a
moment. There are standard 1/4-inch mounting threads on the top and bottom
halves of the case, positioned at or near the centre of gravity, when a lens is
fitted.
Inside the case there’s five PC boards, clipped into a pressed steel
chassis cage. One board carries the very compact mains power supply; two larger
boards contain the video processing microchips, the CCD image sensor and
control electronics are mounted on the fourth board, at the front of the
camera. The fifth board sits behind the rear panel, this supports the two BNC
sockets, one for video output, the other for an external synchronisation (genlock)
connection. Below that there’s a three-pin, spring-loaded terminal block for
the auto-iris lens lead. The mains on/off switch and cable are also mounted on
the back panel. There’s a standard four-pin socket on the side of the case, for
direct-drive lenses and on the opposite side is a mechanical screw adjustment
for setting back focus, to accommodate different lens types. The front of the
camera is almost featureless, apart from the lens mount and a red power-on LED
indicator.
Disabling the LED indicator is one of the options on the larger of the
two concealed DIP switches; other functions include switching the electronic
iris on and off, AGC on/off and high/low sensitivity, backlight compensation
on/off and three gamma correction settings. They are: 0.45 for demanding
low-light conditions; 0.83 for general purpose day/night operation and 1.0, for
computer-based process and medical applications. The electronic shutter has
eight speed settings: 1/50th, 1/125th, 1/250th, 1/500th, 1/1000th, 1/2000th, 1/4000th
and 1/10,000th second. Additionally it has an FL or ‘flickerless’ mode, for use
with auto-iris or direct-drive lenses, when the scene is illuminated by
fluorescent light.
Initial set-up is confined to fitting and adjusting the lens, setting
the back focus, selecting the appropriate exposure options and shutter speed. A
small potentiometer next to the shutter DIP switch sets the control voltage for
direct drive lenses. The rather brief instructions also detail the alignment
procedures for zoom lenses and setting line-lock for multi-camera
installations. Apart from that there’s scant guidance for installers, other
than obvious warnings about exposing the camera to excessive temperatures, and
protecting it from moisture. The case isn’t particularly vulnerable in this
respect, there’s no openings or grilles in the top or bottom, though dust, dirt
and liquids could find their way inside through the side panels, so a
protective housing is advisable if the camera is to be used in the open.
PERFORMANCE
Mono cameras still have a commanding position when it comes to bottom
line decisions regarding resolution, image quality and cost. The 3130 is no exception, under standard test
conditions our sample comfortably exceeded 380-lines horizontal resolution with
an basic 8.5mm lens. The image is very clean, there’s some very slight ringing
after bright vertical picture elements but no visible patterning or striation.
However, this camera really begins to show its mettle in poor light,
with the image remaining clear bright and contrasty long after grain and noise
have started to affect similarly specified cameras. The various exposure
options provide an effective counter to most common lighting problems and the
auto controls are able to deal with most changes, though clearly much depends
on the type of lens used and the care taken during initial installation.
Backlight compensation works very well indeed, increasing available detail on
strongly backlit subjects by a significant degree. The high-speed shutter is
another useful exposure tool, and it can make a big difference to the quality
of still and slomo tape replay, especially if there is a lot of movement in the
scene.
OVERALL
ASSESSMENT
The 3130 is a remarkably well thought-out design with a range of
features that do not confine it to just security and surveillance applications.
The rugged construction makes it eminently suitable for harsh or unforgiving
environments, where the camera may be subjected to mechanical shock from time
to time. The unusually versatile exposure system operates within a broad range
of lighting conditions and there’s sufficient flexibility to enable it to work
with pretty well any type of lens; presettable gamma correction is a welcome
added bonus. The 3130 can be configured to function in a range of CCTV systems,
from simple one-camera set-ups to comprehensive multi-camera
installations. Finally performance;
image quality is very good, and although it’s not being specifically flagged as
a low-light camera it nonetheless gives a very good account of itself in
unfavourable lighting conditions.
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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© R.Maybury
1994 0607
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