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COMPUTAR YC-05 COLOUR CAMERA
COPY
It wasn’t so long ago that installers and
end-users needed some very good reasons to opt for a colour CCTV system; these days
it’s difficult to find an argument not to use colour cameras in all but the
most demanding or specialist applications. Generally speaking the cost
differential is now comparatively small, compared with just a couple of years
ago. Performance is no longer an issue and most recent general-purpose colour cameras
have the same kind of resolution and low-light properties as their monochrome
cousins, moreover they’re no larger, heavier or any more difficult to install.
The new Computar YC-05 illustrates most of
those points. It’s a compact colour camera, designed and built by leading
Japanese manufacturers Chugai Boyeki. Compact is the operative word, it measures
just 110 x 55 x 48 mm and it weighs in at 400 grams (excluding lens). Minimum
illumination is 2.5 lux, and horizontal resolution is quoted at 330-lines. The end-user
price is on the high side though, this is in the region of £390, and that
excludes a lens and power supply.
Design and layout are both very
straightforward, the camera is contained within a tough two-part grey/black metal
case that affords the electronics a fair degree of protection against the
ingress of dust and moisture, a range of weatherproof housings are available
for use outdoors or in harsh environments. At the front there’s a standard CS
lens mount, with mechanical back-focus adjustment that shifts the mounting ring
fore and aft by +/- 2 mm, using a recessed screw on the left side. Once set it’s
locked using a second screw on the opposite side of the camera body. C-mount
lenses can be fitted, using an optional 5 mm adaptor ring. The camera has a
standard square 4-pin auto-iris connector socket on the right side of the body,
(a blank plug is supplied) a three-position switch below the socket configures
the camera for DC or video-controlled auto-iris operation; the third option is a
full-range auto high-speed shutter, for use with a fixed iris lens.
On the left side of the case there’s two further
switches and a pre-set adjustment. The first switch is for selecting sync mode,
which can be either line-lock or internal. The second switch and preset are for
selecting and adjusting the DC iris level, the options are factory pre-set or
manual. On the back panel there’s a single BNC connector, for composite PAL
video output. There’s a second preset, this time for adjusting line phase,
(when used with a camera switcher) and a pair of spring-loaded terminals, for
either 12V DC or 24V AC power supply. The camera’s power requirements cover a
fairly broad range, they are: 10.8 to 13.2 volts DC, or 21.6 to 26.4 volts AC
(using a Class 2 supply). A green LED indicator next to the PSU connector shows
power on.
The YC-05 has a 1/3-inch interline CCD image
sensor with a 500 x 582 (effective) pixel array. In the auto high-speed shutter
mode speed varies between 1/50th second up to 1/2,000 th second. White balance
adjustment is fully automatic and power consumption is rated at a maximum of 5
watts.
Internally the standard of construction is
very high with the main circuit boards mounted on a rigid alloy chassis. The
boards themselves contain a high-proportion of surface mounted components,
resulting a solid assembly that should be able to withstand a fair amount of
mechanical shock and vibration
The camera comes supplied with an ABS mounting
plate, fitted with a standard 1/4-inch UNC thread, it’s attached to the
underside of the case by two screws. It can be removed and screwed to the top,
to suit different types of mounting hardware.
Installation poses no problems; the unusual push-fit
power supply terminal provides a secure anchorage for the cables. There are few
preliminary adjustments, apart from fitting the lens, auto-iris set-up and
line-phase in multi-camera systems. The supplied multi-lingual instruction
booklet is fairly typical, that’s to say it’s rather sparse, not very well laid
out, with only brief summaries concerning the various operations, nevertheless experienced
installers shoudl be able to follow it without too much trouble.
PERFORMANCE
Tests were carried out using a 8.5 mm f1.5
Computar manual iris lens, this gave a horizontal resolution figure of just
over 330 lines. Picture noise levels were very low, similarly in good light colour
noise was insignificant, even on areas of high saturation. The camera’s auto
white balance system worked well under a range of lighting conditions. It’s optimised
for natural light but it coped easily with most forms of artificial light,
including mixed light and often troublesome tube lighting, with only a very slight
green-yellow colour caste. Colour fidelity was generally very good in natural
light, though it does tend to slightly over-emphasise reds and greens.
The auto high-speed shutter is very smooth,
and it responds quickly to sudden changes in illumination levels. Low light
operation is average to good, it will produce a useable image under typical street
lighting conditions, though noise levels are high and there’s a fair amount of
grain in the picture. Bright highlights in the picture area produce a characteristic
streaking, and as usual some care needs to be taken during alignment to avoid
problems as lighting conditions change throughout the day and night.
OVERALL ASSESSMENT
In performance terms the YC-05 compares favourably
with the current crop of compact colour video cameras. Feature-wise it doesn’t
have many particularly notable talents but it’s unobtrusive and can cope easily
with most routine conditions. It can be fitted with a wide range of lenses and is
sufficiently flexible to integrate with a variety of systems. The price is
fairly unremarkable, though given it’s pedigree and the quality of construction
it is worth considering as a general purpose camera for routine applications.
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 1995 0108
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