ES31C ESPRIT INTEGRATED CAMERA
WHAT OUR EXPERTS SAY...
If there's one thing most security installation engineers dread it's
messing around with a dead camera on the top of a twenty-foot pole or some even
more treacherous location. Add in the British weather and the security
industry's version of Sod's Law (there will probably be nothing wrong with the
camera and the fault will always be in the last place checked…), and you have a
very convincing argument for a product like the Pelco ES31C, a rugged and fully
integrated motorised camera system from a company with an impeccable pedigree
and track record for dependability.
The keyword here is 'integrated' which rightly suggests that the camera,
its motorised mount hardware and associated systems are all designed from the
ground up to work together. This has major implications for ease of
installation, configuration and long-term reliability. That's not meant to
imply that motorised camera systems assembled from components made by different
manufacturers are inherently less reliable but there is a good chance
installation times will be longer and control systems will necessarily be more
complex, or less flexible, or both.
The EC31C is a member of Pelco's Esprit family of products, it is rather
grandly described as a 'Positioning System with IOP' (Integrated Optics
Package), otherwise known as a pan/tilt head with built in camera and lens… The
particular model we have been looking at is the ES31CBW18, which is the top of
the range version with a high resolution colour camera featuring an 18x optical
zoom and 4x electronic zoom plus a built in window wiper; models with black and
white cameras, a range of zoom options and with and without wipers are also
Starting with the camera section specs, our sample has a F1.4 lens with a
4.1 - 73.8mm focal length. Low light sensitivity is quoted as 0.2 lux (slow
shutter mode), the 0.25-inch interline CCD, has a 752 x 582 pixel array giving
a claimed resolution of around 460 lines. Focus, exposure shutter speed and
white balance are fully automatic (with manual overrides). The camera is
remotely configurable via a menu-driven on-screen display system, the main
options are auto focus on/off, auto iris (auto/manual, iris level & peak
level), switchable IR filter and level, backlight compensation with adjustable
sensitivity area and variable gain/AGC. Picture sharpness and shutter speed can
also be manually adjusted. The
on-screen displays also cover programming the motorised head functions and
positioning and we'll look at that in more detail in a moment. To round off,
the front window has a built-in heater/demister and the whole caboodle is
powered by an external 24 volt AC supply (120/230 volt models are also
The imposing and very sleek looking pan/tilt assembly has an equally
impressive specification, pan speed is variable, between 0.1 and 40 degrees per
second variable speed and 100 deg/sec in 'turbo' mode, with proportional pan
and 360 degrees rotation. Vertical tilt is from –90 to + 40 degrees at 0.1 to
20 deg/sec variable speed. Preset pan/tilt speeds are 100 and 30 deg/sec
respectively. General operating parameters are a safe temperature range of -45
to 50 degrees centigrade (60 degree C tolerable for short periods) and it will
remain operational in wind speeds up to 90 mph and withstand up to 130mph,
though whether or not whatever it is bolted to will stay upright in such
conditions is open to debate...
Camera set-up and the motorised mount functions can be controlled and
programmed using a wide range of Pelco system components (video
switcher/controllers CM6700/8500/9500 & 9760 and keyboard units KBD200/3000
& 300V), for the record our review sample was used with a CM6700 matrix
camera switcher and KBD300 Universal keyboard. The EC31 can communicate with
its control hardware using either RS-422/RS-485 protocols, or Pelco's
proprietary Coaxitron system, which uses the video connection to carry
telemetry and data to and from the camera; note that some setup and control
functions may not be accessible using some combinations of components.
The standard of construction is high. The camera housing is made from
heavy gauge die cast and sheet alloy materials, the finish is very good indeed
and it is clear that a lot of attention has been paid to weatherproofing.
Access to the camera's innards is via a hinged, spring-loaded panel on the top
(complete with padlock fittings). Once open the all-in one camera module or
'sled' can be easily lifted out with just one hand (worth knowing when you're
perched on top of a ladder thirty feet above the ground). The pan/tilt
mechanism is superbly well engineered and looks as though it'll withstand just
about anything the British climate (and vandals with good aim…) can throw at
it. It has two gearless drive trains, using toothed nylon belts, which
undoubtedly contributes to its smoothness, quietness of operation and
impressive turn of speed. Camera and motor controls and the communications
electronics are all mounted on a single PCB housed in one of the two side
lobes, access to either side of the unit is via a single captive screw.
Re-fitting the covers and aligning the seals can be quite tricky though, so
it's a good idea to carry out any adjustments on the ground (there's a pair of
DIP switches for setting communications protocols).
SETUP AND OPERATION
Installation is unlikely to pose too many problems for experienced
engineers, and like the rest of the unit the mounting hardware is very well
engineered, functional and easy to use. The same goes for the instructions,
which appears to have been written by someone who actually knows what they are
talking about. The unit connects to the outside word using a single, small
multi-way plug on the end of a flying lead emerging from the base of the
pedestal; this mates with a socket mounted in the top of the transformer
module, which once again contributes to easy installation and maintenance.
The remainder of the on-screen menus, mentioned earlier, are mostly
concerned with programming the unit's motion and movements. The options include
setting limit stops, tour pattern length (1.5, 3 or 6 minutes, or two
half-patterns lasting 45 seconds, 1.5 or 3 minutes), action on power up
(default configuration, park on preset 1, auto scan, random scan, full pattern,
and half pattern 1 or 2). Panning motion can be set to normal or proportional,
which basically means the pan speed slows down at higher zoom settings. Limits
can be set on scanning speed (1 to 40 deg/sec) and there's an option to reset
the unit to its factory defaults. A feature called speed profile allows the
operator to adjust the unit's behaviour in wind speeds of 50 or 90mph (sets
limit on pan/tilt speeds at higher wind speeds), and there is a set of wiper
adjustments (momentary wipe, variable
dwell time and wipe duration).
Image quality is very good indeed and our sample performed at or close to
the manufacturers specifications. Resolution was within a whisker of the stated
figure and colour accuracy remained stable under mixed lighting and sudden changes
in scene lighting. In low light conditions the camera automatically switches to
black and white mode and it continues to produce a useable image in quite
difficult conditions. The electronic zoom takes over seamlessly when the
optical zoom reaches the end of its travel; there is a tiny increase in noise
levels but in good light it is barely noticeable. The only minor quibble
concerns the speed at which the camera returns to colour when light levels
increase, it can be very slow and occasionally it is necessary to 'nudge' it by
pointing it at a brightly lit area. Noise levels in all operating modes are
well below average and only become significant at the limits of the cameras
operating range. The auto focus, exposure and white balance systems proved to be
very agile, requiring a minimum of manual intervention.
The pan/tilt mechanism operates flawlessly; it's fast and highly
responsive to the joystick control –
turbo mode is most impressive -- yet it is able to move in minute increments.
The motion is smooth and controlled with out the slightest suggestion of lag or
overshoot, though it does put on an unexpected turn of speed when it shifts up
a gear into turbo mode, at around the halfway point on the joystick's travel.
There's every indication the ES31C will provide long and faithful
service. Everything about it says quality and attention to detail, from the
obvious effort that has been taken to weatherproof the unit, to the
over-engineered wiper mechanism. Mechanical construction is matched by the
video performance, which ensures the camera will produce a detailed,
well-balanced image more or less autonomously under the widest possible range
of illumination levels.
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 ??
ã R. Maybury