multiplexers have become an indispensable tool in small and large-scale
multi-camera systems. The Montage range of multiplexers from Vision Factory
offers specifiers, installers and end-users some unique facilities.
multiplexer technology has advanced in leaps and bounds during the past few
years, bringing with it significant improvements in performance and versatility
as well as some very welcome economic benefits. However, a lot of products on
the market appear to have quite similar sets of specifications. The Montage
range of multiplexers, from The Vision Factory, is different though, broadening
the choice for installers and end users, particularly on larger systems, using
up to 32 cameras.
Many of the
options on the CD24 (24 camera colour duplex version) multiplexer we’re looking
at here, will be familiar. They include a range of standard display formats;
there’s 2x2, 3x3 and 4x4 screen layouts, but in addition there’s a 5x5 display,
plus a range of composite patterns, that ultilise a mixture of screen sizes.
The facility to customise displays -- Vision Factory call them ‘presentations’
-- by positioning different-sized sub-screens anywhere on the display is also
highly unusual. This enables operators to make the most efficient use of a
monitor display, to suit the conditions and surveillance priorities, and ease
the operators workload.
a key feature. Each camera input has an associated monitor output, additionally
there are a range of monitor and VCR outputs with provision for component (Y/C)
and RGB outputs, for the main monitor. This will ensure maximum picture
performance from colour cameras, moreover the RGB output will give the best
results when the system is used in conjunction with a colour video printer.
Live camera or
off-tape images can be frozen and zoomed for display and analysis purposes, or
to produce hard copies. Duplex operation enables off tape images to be reviewed
while normal multiplex recording continues. Multiplexers in the Montage range
have a full set of alarms, associated with each camera input and the system
reacts to video loss or camera failure. Alarm status is displayed and recorded,
and activation’s are displayed during replay. Camera channels have their own
user-definable idents, along with a time and date display.
configuration, picture settings and set-up routines are controlled from a
simple to use menu-driven on-screen display system. Settings are permanently
stored on an EPROM and protected against power failure. Access to the system
and accidental or deliberate interference can be prevented using a control lock
that’s activated by a 4-digit PIN code.
The CD24 is
housed in a sturdy rack-mountable steel case measuring 440 x 440 x 90mm. The
front panel keyboard is detachable for remote operation (up to 100 metres
distant), a front panel blanking plate is supplied when this option has been
output socketry is grouped together according to function on the back panel.
Camera inputs and outputs are arranged in pairs, each set of 8 input and output
sockets is associated with a bank of miniature DIP switches, that select the
appropriate termination for used and unused outputs. On the right side of the
back panel are the monitor, VCR, external control and alarm connections.
Composite video feeds are handled by standard BNC sockets; Y/C and RGB signals
are clustered together on a pair of 15-pin D-sockets.
The front panel
controls are in four groups. Main functions (live, replay, record and tape
monitor) buttons are on the left side. A row of 12 ‘function’ keys running
along the lower edge of the panel selects the various ‘presentation’ screen
displays. To the left there’s a bank of 12 keys for selecting individual camera
inputs, zoom and freeze functions, and sequence display for a spot monitor. The
numeric keypad on the far right is used to nominate camera inputs, PIN number
entry, and there’s a set of cursor buttons, to control the on-screen display.
display is used primarily to configure the system and select various
sequencing, alarm and ident options; once set most routine operations can be
controlled from the keypad without reference to the on-screen displays. Montage
is designed to be used in conjunction with time-lapse VCR and again there are
numerous options, based around different types of machine. The system does not
require programming to operate with a particular make or model of VCR, giving
it the maximum flexibility to work in a variety of configurations. This
includes installations where machines are cascaded, to make the most efficient
use of tape, and minimise the effects of longer delay times, associated with
more complex multi-camera systems.
have used some of the latest generation of digital video processing microchips,
that ensure clean resolution and good colour fidelity, even on the smallest
sub-screens. The multiplexer is relatively transparent to the signals passing
through its processing circuitry. Inevitably some artefacts are visible, and
some detail is lost, though it is relatively insignificant, and comparable with
most other multiplexers on the market. Luminance and chrominance noise levels
in all display modes are very low, images appear clear and well defined, though
a lot will depend on the capabilities and characteristics of the cameras,
monitors and video recording equipment it is used with.
Montage is a
competent, well-designed system that’s
easy to install, configure and use. The range of options caters for the widest
possible range of applications and the system’s flexibility, particularly when
it comes to the variety of display functions is most impressive. A definite
step forward in the field of large-system multiplexers.
BOX COPY 1
Video system PAL
colour, CCIR black and white
Screen formats 5 x 5, 4 x 4, 3 x 3, 2 x 2, multi combination, PIP,
Video level: 1.0
volt p-p, 75 ohms (composite)
Video in/out composite,
component Y/C or RGB
input per camera (N/O or NC contact)
Alarm output output
relay 1.5A N/O and N/C contacts
in/out, monitor & VCR BNC, S-Video, RGB alarm and RS232/RS442 external
control (D connectors)
requirements 110/2410 VAC
50/60Hz, 50 watts
x 440 x 90mm
BOX COPY 2
Product design 8
Build quality 8
Ease of use 8
Image quality 8
Ó R. Maybury 1996 1907