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NORBAIN VISTA NPX16e VISION MULTIPLEXER
STANDFIRST
No, it’s not a high-priced Scandinavian hi-fi system, or the
latest video game console, this is a serious piece of surveillance kit, really…
COPY
Strange as it may seem, and all evidence to the contrary,
there are no rules governing the external appearance of video surveillance
equipment. Cameras are designed to be discrete, or obvious, depending on the
application, but what about the ancillaries?
There seems to be some sort of unspoken consensus amongst manufacturers
that everything connected with video surveillance – whatever its purpose --
must be housed in off-white, square cornered boxes and look as bland as
possible. Perhaps they’re worried operators will be distracted by a dash of
colour? More likely it’s just cheaper and easier to do it that way. The point
is, when someone dares to be different, it really stands out, like this Vista
vision multiplexer from Norbain.
Simply looking different isn’t enough; this is a serious
business for heaven’s sake. So how well does this dramatically styled
multiplexer stack up against it’s less flamboyant rivals? Once you get past the imaginatively
contoured black case with its bright blue buttons, it’s off to a very good start,
if the feature list is anything to go by. There are two versions at the moment:
the NPX16e, that we’re looking at here, has 16 camera inputs; a 10 camera
variant is also available (NPX10e), though you can take it as read that apart
from the number of video channels, operationally and functionally they are
identical.
Both models operated in what Vista describe as Triplex mode.
It has nothing to do with car windscreens but indicates that it a notch up on
conventional duplex multiplexers, which can simultaneously playback a
multiplexed tape, and continue recording (on a second VCR). Triplex operation
means the NPX16e can display live images and playback off-tape recordings on
one of its two monitor outputs, and continue to record, all at the same time.
The Triplex facility utilises one of the NPX16e’s seven
multi-image display modes. The options are PIP (picture in picture) with a
moveable sub-screen superimposed on a full-screen image. There’s a conventional
quad (2 x 2) display with the screen divided into four. The 7-way display is
similar to the quad, except that one of the quarter screens is further
sub-divided into four. A 9-way or 3 x 3 display shows nine images. The 10-way
screen is a quad display with both lower quarter-screens divided into four. A
13-way screen is a quad with three of the quarter screen showing quad images,
and lastly, there’s the 16-way or 4 x 4 screen, showing all connected
inputs.
Each video channel has an associated alarm input that, if
activated, closes a relay and modifies the recording sequence. This uses a technique
known as time division multiplexing whereby the output from a triggered camera,
(or cameras), are recorded more often than the other cameras. Additionally each
camera channel has its own motion detector alarm system. This will also alter
the recorded sequence if activated, to favour cameras where activity has been
detected. The motion sensor divides the
screen into a 16 x 16 grid of 256 sensor zones, which can be alternately enable
or disabled. The motion sensor facility can be used in one of two ways, to
discriminate between activity (changes in luminance) and intrusion (movement).
In addition each camera has 10 levels of sensitivity plus a three-level false
alarm rejection setting.
All connected cameras can be sequenced and displayed on the
two monitor outputs, dwell time is variable. Monitor B shows only a full frame
analogue image from the sequence or the output from an alarm activated camera.
Monitor A displays a single or multiple image, the Triplex display and the
on-screen menu. Other important
features include an electronic zoom (more about that in a moment) and an
activity log that records details of the previous 100 events. The unit
generates a camera ident for each channel and it has a built-in telemetry
transmitter, to remotely control camera focus and iris, plus PTZ (pan/tilt and
zoom) functions and installations with lights and wash/wipe facilities.
The on-screen display and set-up routine are password
protected, mono and colour camera operation is automatically selected. Up to 32
functions can be sequenced and controlled by a simple two-button command using
a macro programming facility (macros can also be triggered by an alarm
activation). Each camera has it’s own AGC setting and a video loss alarm.
Summer and Winter time changes can be made using a single button and there’s an
option to connect the NPX16e to a radio time receiver, controlled by the Rugby
atomic clock. All user-programmed settings are protected against power failure
by battery-backup.
There’s no doubt that it is a very unusual looking case,
it’s a two part moulding made from ABS plastic, and measuring 460 x 88 x 390mm.
The flat top is just the right size and strong enough to support one or more
time-lapse VCRs. The highly distinctive front panel is populated with bright
blue buttons, several of them with adjacent LED indicators.
Control layout is borderline haphazard. There’s no problem
with the row of 16 camera buttons along the top edge, though they could do with
activity indicators, rather than having to rely on the on-screen idents, which
can be very small on a multi-screen display. Some of the keys do not seem to
follow any clear pattern. On the left side there are controls for macro
programming, operating mode and camera functions. In the middle there’s a large
blue button that’s responsible for cursor control on the on-screen display, and
pan/tilt action. To the right of that is a mixture of picture controls (freeze,
multi-screen) and housekeeping functions, like camera wash/wipe and lamps
on/off and monitor select. You can learn to live with it, but there’s a
distinct feeling that it could be a lot better.
In case you’re
interested, inside the box there are four printed circuit boards, the
Two largest ones are in
the middle of the cabinet, one on top of the other. They deal with video
processing the alarm functions and power regulation. There’s a smaller PCB at
the rear, this handles all of the input and output connections, and the board
at the front is for the controls and indicators. Everything looks reasonably
easy to get at, surface mount components are used throughout, for maximum
reliability, and it runs cool, thanks to a small, and reasonably quiet fan on
the right side of the case.
SET UP AND USE
After the multiplexer has powered up and run through a brief
self-test, a 4 x 4 display appears on monitor output A, showing all active
camera inputs. A multiplexed output of all video channels appears on the VCR
output. To change any of the default settings it is necessary to enter a simple
password to access the menu-driven on-screen displays. Page one covers all of
the main options, selections are made with a moving cursor (via the big blue
button); pressing the 'Enter' button normally brings up a second or third
sub-menu, from which various options can be selected. Key set-up operations
include setting the time and date, enabling active camera inputs, creating
camera idents, setting up any motion detector zones, alarm and video loss
actions, VCR set-up and camera AGC. Navigating around the menus is quite easy,
though some operations can be a bit time-consuming.
Most non menu-controlled operations are either
straightforward or self-explanatory, though the slightly eccentric control
layout can sometimes lead to confusion. The instruction manuals can be a bit
heavy-going at times, the information is all there, but finding it can
sometimes be a problem.
There are two basic operating modes: only the outputs from
alarmed cameras are recorded in the Exclusive mode, whilst all camera outputs
are recorded in Interleave mode. During off-tape playback the unit shows a
multi-screen image of all cameras, from there a single image can be chosen, or
any one of the multi-screen options. The electronic zoom feature is unusual;
this works on a live recorded or frozen picture. Pressing the zoom button
magnifies the displayed image by a factor of 2X; the pan and tilt control can
then be used to view any part of the picture.
Alarm activation, whether from one of the external inputs or
via a camera motion sensor, switches the display on monitor A to full screen
(or quad, if more than one alarm is triggered). Monitor B switches to the
output from the alarmed camera. The sequence of images that are passed to the
recording VCR are changed to increase the number of times the output from the
alarmed camera is included. At the same time an internal buzzer sounds, an
on-screen indicator appears, a warning LED flashes on the front panel of the
multiplexer and one of two relays are energised. There are various alarm-reset options. It can be set to latch, so
that it can only be cancelled by an operator.
Alternatively it can be set to time-out (unless the alarm condition
remains), or set to transparent mode, where it will automatically clear, once
the alarm input has ceased. The second alarm relay is activated by a loss of
video on any one of the camera inputs, or by a motion detector.
PERFORMANCE
Despite all of the heavyweight digital video processing
going on inside the box there is no noticeable reduction in resolution, or any
significant increase in picture noise, between the video input signal and the
output, to the recording VCR. Picture stability and colour fidelity are both
very good indeed, though we did notice a very small decrease in colour
contrast. When camera outputs are viewed in the live mode there’s a choice of
field or frame-rate display; some flicker is evident in the frame mode, which
can be quite distracting, and tiring to watch for more than few seconds at a
time.
In the end any degradation in picture quality will be caused
by the recording VCR. The NPX16e does have Y/C (S-Video) outputs for the
monitor and a Super VHS VCR, though in order to get full benefit from Y/C
processing, the camera should be included in the Y/C signal processing chain as
well. However, since the NPX16e only has composite/CCIR inputs, some of the
potential improvements that would result from the use of high-specification
cameras, are lost.
SUMMARY
When it comes down to it the cosmetics of a particular
device or piece of surveillance equipment are secondary to performance;
nevertheless, there’s a lot of truth in the old adage that when something looks
right, it usually is. The shape and styling of the NPX156e may be a little
unconventional, but it does look right and it is completely practical. The
extra frills and colourful buttons do not in any way detract from its real
purpose. As multiplexers go it is an advanced design, with above average
flexibility and performance, plus numerous extra features, that can only
enhance its operational capabilities.
PRODUCT SPECIFICATION
Power supply 12 VDC (AC mains adaptor supplied)
Weight 4.5kg
Dimensions 460 x 88 x 390mm
PSI RATINGS
Product
Product design 9
Build quality 9
Ruggedness 8
Operation
General functions 9
CCTV functions 9
Ease of use 7
Instructions 7
Manuf. support ?
Performance
Video quality 9
Switching 9
Audio n/a
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R. Maybury 1998 1603
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