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The layout of general purpose video surveillance cameras has changed little in the past thirty or so years. The overwhelming majority of them still comprise a fixed lens attached to a box, containing the pickup device and video processing circuitry. Admittedly there has been a major revolution in image sensors and electronics over the last few years, but the design and construction of camera lenses has remained virtually unaltered, since the C-mount fitting was first introduced in the 1920s. The Mitsubishi CCD-200 colour video camera marks a significant change in design philosophy, not only is the lens built inside the body of the camera, it has been equipped with power zoom and auto-focusing facilities. This approach gives the installer and end-user far more flexibility over camera location and targeting, it also eliminates the need for specialist lenses, and opens up a range of new possibilities in remotely controlled surveillance systems.


The CCD-200 was designed in collaboration with Mitsubishi’s consumer division, the lens assembly was originally developed for use in the company’s domestic camcorders. It incorporates a motorised 8x zoom, controlled by a pair of buttons on the rear of the case. The module contains a full-range inner-focus lens system, with a focal range extending from 1cm (wide-angle) to 80cm (telephoto). The sensor is a high-performance 1/3-inch CCD with a 470k pixel array (440k effective) and it will produce a useable image down to light levels as low as 1 lux, (in the gain-up mode).


Although the lens unit is extremely compact, it has meant that the case is slightly taller than usual, however, because the optics are built-in are no frontal projections, so it is no longer than a normal compact video camera plus lens. Overall it measures 145 x 76 x 4.6.5 mm, and weighs just 490 grams. The front of the lens is fitted with a 37mm filter thread; Mitsubishi have no immediate plans to make use of this facility, but it can be used to mount a range of wide-angle and telephoto adaptor lenses,  intended for camcorders. In addition to the two zoom buttons the rear panel has two further buttons (for on-screen display, and auto-focus); in addition there are sockets for composite and S-Video (Y/C) output and DC power-in socket, plus a green power-on LED indicator. Standard mounting threads are fitted to the top and bottom of the steel case. The camera is powered by an external 12 volt DC supply.


The CCD-200 has a number of additional features, accessed from a menu-driven on screen display. They are: pre-settable white balance, shutter-speed, backlight compensation, camera ident and manual or auto-focus. The white balance options include auto and lock; in the auto mode the camera adjusts the white balance according to the prevailing lighting conditions. The lock mode is used to fix colour balance to a white reference, typically a white card or sheet of paper placed in front of the lens. It has two further presets, for natural (outdoor) and artificial (indoor) lighting. The electronic shutter has a range of 7-speeds, from the ‘normal’ setting of 1/50th second, to 1/10,000th of a second. The backlight compensation adjustment has three settings: off, on and gain-up, the latter increases the camera’s low-light sensitivity. A camera ident can be superimposed on the bottom right hand corner of the image, the display shows a letter ‘C’ followed by a number which can be set from 1 to 16.  


When the camera is switched on it displays a focus set-up message, which indicates that it is returning to the last pre-set position; white balance and shutter settings are also retained in the camera’s non-volatile memory when the power is removed. The initial alignment procedure is very straightforward. White balance, shutter speed and backlight settings are selected and set from the menu. The focus options are on a second menu screen; when this is displayed the zoom buttons are used to adjust the focus manually, alternatively the autofocus system can be momentarily engaged at any time, by pressing the focus button on the back of the case. If no selections are made after 30 seconds the menu disappears and the camera reverts back to normal operation.


On the CCD-200 the adjustments have to be made with the camera in-situ, however, Mitsubishi have recently introduced a second version, (CCD-300), which has an RS232 serial port, enabling all of the camera’s main functions to be remotely controlled from a dedicated control unit. This model would be particularly suitable for installations in inaccessible locations, or used as part of a more wide-ranging surveillance system, in conjunction with a motorised pan/tilt head. Both models have an end-user price of £780.



Using a Y/C feed between the camera and a colour video monitor (we used a Mitsubishi EM1490 for the tests), the CCD-200 managed to resolve in excess of 430-lines. Changing to a composite feed resulted in a small reduction in picture detail and resolution fell to just over 380-lines. In both cases picture noise levels were very low, though on composite video hook-ups there was a slight increase in patterning around fine detail. Colour fidelity in good natural light is excellent, bright reds are slightly overstated, but there is no noticeable spillage, or mis-registration. In lower light levels colours loose vibrancy and there is an increase in noise but the image remains coherent. The auto WB system copes well with most forms of artificial light, though tube lighting needs care, and should be set manually using the lock option as it can result in a slightly yellowish caste. The manual focus controls are reasonably well-damped, minimising overshoot, but unless the scene contains multiple or moving targets, the autofocus system can be relied on to produce a sharp lock almost every time.  



The CCD-200 is a remarkably versatile design, well suited to a wide range of applications, from security to audio-visual presentation. Mitsubishi also tell us they are considering plans to incorporate the camera into teleconferencing systems, indeed, using one as a fixed-scene surveillance camera would be a sad waste of its talents, though undoubtedly that’s a job it does extremely well, moreover the zoom lens frees the installer from having to choose a specialist lens for each location. There is a price premium to be paid, though in some circumstances it may be relatively small, compared with the cost of a similarly specified camera and separate lens.  




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                                                     




Ó R.Maybury 1995 1705






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