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BAXALL CDSP 9713 & 9752 VIDEO CAMERAS
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WHAT OUR EXPERTS SAY...
There's an instant sense of deja vu with these two cameras
from Baxall. The CDSP 9752 and 9713
look almost identical to the Baxall CD9252 and CD9312 cameras that we reviewed
a little over two years ago. They're an identical configuration: one is colour
(9713), the other is black and white (9752) and both are mains powered (12 volt
DC and 24 volt AC variants are also available). The similarities continue,
right down to the fact that the average power consumption for all cameras --
1996 and 1998 models -- is 5 watts. There are differences however, and some of
them are quite significant, though the designers clearly have a lot of faith in
the old maxim, that 'if it 'ain't broke, don't fix it'!
But first the basics, both cameras are built inside in cream
coloured housings measuring 123 x 67 x 60mm. The only distinguishing features
are an extra BNC socket on the rear of the 9752 (for external genlock) and the
9713 has a multi-coloured flash on the side, denoting it is the colour model
(the 9752 has a grey stripe). On the right side of both cameras there is a
hinged flap that opens to reveal a rotary adjustment -- for video level setting
on an auto-iris lens -- and a 10-way miniature DIP switch. This is one of the
very few external differences between this and the 96 vintage models. They had
two separate DIP switches, the new arrangement has no apparent operational or
ergonomic advantages, but it must help with the manufacturing costs.
To the right of the control flap there's a square 4-pin auto
iris socket. The front, top and bottom halves of the case is made from
lightweight alloy castings and extrusions; the front cover and end cap are moulded
from ABS plastic. Threaded mounting bosses are fitted to the top and bottom
case sections. The quality of construction is very good and the assembly is
remarkably strong. The case parts fit together neatly but there has been little
or no attempt to protect the housings from moisture, dust or airborne
contaminants, so they are only suitable for indoor installation, in a
reasonably clean, camera-friendly atmosphere. The lens mount is a multi-format
(C or CS) type with an elaborate back-focus/lens type adjustment that can be
set from the top or the side. On the rear panels there are BNC sockets for the
video output, a spring terminal for direct-drive auto iris lenses, a green
power on LED, a recessed preset adjustment for line-level phase and the captive
mains power cord.
The DIP switches cover a wide range of functions. Positions
1 and 2 are for not used on the 9752 but on the 9713 they're for setting white
balance; the options are full auto, indoor, outdoor and fluorescent. On both
models SW 3 is for gamma correction, the choices are normal (0.45) and linear
(1.0). SW4 enables the AGC, SW5 switches between fixed or adjustable line-level
phase, SW6 toggles between line level or internal synchronisation. Switches 7
to 10 are concerned with the electronic shutter and iris modes. When SW7 is in
the down or off position switches 8, 9 and 10 are used to select a shutter
speed between 1/50th of a second to 1/10,000th sec, in 8
steps. When SW7 is in the up position SW8, 9 and 10 select electronic iris,
backlight compensation and flickerless modes.
Two years ago, when we reviewed the CD9252 and CD9312, we
noted that there were marked internal differences between the colour and
monochrome cameras, this time around they're much harder to spot. Inside both
cameras there are four printed circuit boards. The power supply board lives on
the bottom of the case, it supports a mains transformer that accounts for
almost a third of the internal volume of the camera. The board on the back
panel handles the sockets and switches. Almost all of the video processing is
carried out by board number three on the right side of the camera, the same
board (with some differences in the chipset) is used in both cameras. The
designers have made more extensive use of digital processing circuitry, to
reduce picture noise levels and increase the amount of detail in the image, but
more about that in a moment.
The PCB at the front holds the CCD image sensor; this is
connected to the main board by a short ribbon cable. Both CCDs are 1/2-inch Sony
Hyper HAD types, the colour model has a
stated resolution of 480 lines and a low-light sensitivity of 0.8 lux (F1.2).
This is another change from the previous model, which has a low light
sensitivity of 2.5 lux (F1.2) and a resolution of 460 lines. There's a
difference in the performance figures for the 9752 and its predecessor. This
time low light sensitivity is quoted at 0.08 lux, (compared with 0.1 lux for
the 9252); resolution stays the same, at 580 lines.
OPERATION
The design and layout is very conventional and we cannot
foresee any major installation problems. The only minor difficulty concerns
access to the DIP switches, once the camera is in position. It's fiddly at the
best of times, the switches are microscopic and a tiny screwdriver is necessary
to make any adjustments. It will be even more awkward if the right side of the
camera is positioned close to a wall. The initial set-up is straightforward and
mostly concerned with fitting and adjusting the lens and selecting the
appropriate exposure compensation mode (electronic iris/auto shutter, DC
control or video level auto iris). On the colour camera there's a choice of
white balance control, with auto-tracing for lighting conditions that change
and three fixed settings, to suit different types of light. The other options
are mostly concerned with configuring the camera to work with different types
of switching systems.
The instructions are fairly brief but all of the information
most installers will need is there and easy to find. Baxall have tried to make
the installer and end user's life as simple as possible and the design of the
camera is such that there's likely to be very few questions but just in case,
they've thoughtfully printed their Helpline number next to the DIP switches.
PERFORMANCE
Low-light performance on the 9752 is most impressive, and
significantly better than its predecessor. It really shows up in marginal
conditions; in poor light, when the noise level in the images produced by most
comparable monochrome cameras start to climb. In these circumstances the 9752
is getting its first wind, and will continue to produce a usable picture long
after most other cameras have given up. That alone would be enough to justify
this camera in demanding applications but there's more. It copes equally well
with changeable conditions and scenes with a wide illumination range or spot
lighting. Resolution is as advertised, under typical daylight/interior lighting
levels the picture is very crisp with lots of detail and a broad contrast
range. Picture noise levels appear to have been reduced, not that they were
particularly bad to begin with, however the image does appear to be slightly
cleaner and fine detail is rendered more clearly. The manual exposure
adjustments are there if needed for really tricky situations, but if our sample
was anything to go by, they're unlikely to get much use as the auto settings
are able to compensate for all but the most extreme situations.
Increased low light sensitivity also happens to be the key
feature on the 9713 colour camera. It's a big increase too -- when compared
with the CD 9312 -- putting it on a par with a lot of mid-market mono cameras.
As the lighting level approaches the lower end of the cameras range the images
changes to monochrome, and there is a rapid increase in grain and noise but the
picture remains coherent until it disappears. In normal natural light colours
are crisp and well defined, the auto-tracing white balance system works well
and colour fidelity is very stable. The fixed WB indoor settings work fine in
tungsten light, the fluorescent mode produces a very slight yellow tint but
it's not enough to be concerned about. Noise levels are also down and this is
immediately apparent in areas of high saturation. These can tend to look quite
'busy' with significant dot agitation. There is still some slight 'fizz' with
this camera but it is nowhere near as pronounced, compared with most comparable
models. The auto iris/exposure systems on the two cameras respond quickly to
changes in lighting and changes in shutter speed are sufficiently numerous and
well spaced to prevent 'stepping'.
Both cameras were mechanically stable with no picture
disturbance whatsoever when subjected to our standard intermittancy test (a
series of hard taps with a small rubber mallet…). The back focus adjustment is
pretty solid too and unlikely to drift, even if the camera is subjected to a
high level of vibration. Both of our test samples ran quite warm -- the
transformer actually gets quite hot.
OVERALL ASSESSMENT
The designers have taken an evolutionary approach with this
range of cameras and it has paid off. Last time around we commented that they
were functional, solidly built with an impressively wide range of exposure and
lens options. We're please to report that nothing has changed. The differences
between this years models and the class of 96 are mostly to do with performance
and they are clear to see, with markedly better low light sensitivity plus some
worthwhile tweaks to resolution and picture noise levels. The result is a
clearer, sharper image under a wider range of conditions. The cameras are easy
to install and although the set-up could be simpler, it shouldn't create any
problems in the vast majority of cases. The specification and features list
isn't as extensive as some comparably-priced models but what they lack in bells
and whistles, they make up for with better than average picture quality and
flexibility.
PRODUCT ASSESSMENT
Design and design features 4
Circuitry and components 5
Ease of installation and wiring 5
Range and variety of functions 4
Accompanying instructions 3
Technical advice and backup 4
Value for money 3
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R.Maybury 1998 0607
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