JVC TK-C600 COLOUR VIDEO CAMERA

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Until fairly recently most CCTV cameras have been designed for fairly specific applications, though with the increasing demand for video surveillance there is clearly a growing need for realistically-priced multi-role cameras, that can operate in as wide a range of conditions and environments as possible. JVC have attempted to meet this need with the TK-C600, a flexible and compact high-performance colour camera.    

The TK-C600 is based around a single 1/3-inch interline CCD image sensor with a 320k pixel array, of which 300k pixels are used to generate the picture. Low light sensitivity with an f1.2 lens is quoted at 1.5 lux and horizontal resolution is in the order of 330-lines. The camera can be used with almost any type of lens, including fixed and manual iris types, as well as both DC and video-controlled auto-iris lenses.  Exposure is fully automatic, but there are overrides for the variable-speed electronic shutter, backlight compensation and auto-tracking white balance. Power supply requirements are unusually flexible, it can be run on a 12 volt DC or 24 volt AC supply without adjustment, power consumption in both cases is 4-watts. A mains-powered version (TK-C601) is also available. Synchronisation is internal, though there is a line-lock option, when it is used with a 50Hz AC supply.

The TK-C600 is housed in a rugged two-part steel casing measuring 115 x 70 x 55mm. The case offers little protection against the ingress of dust or moisture, so it will be necessary to use a suitable enclosure, if it’s to be used in a hostile environment. The design is simple and uncluttered. At the front there’s the threaded lens mounting collar. Behind that is the CCD image sensor, located on a sliding back-focus assembly. This has a fore and aft movement, that will accommodate both C and CS-mount lenses. The setting is changed by turning a large thumbwheel, a small portion of which protrudes through a slot in the casing. Differently shaped mouldings on the rim of the ring denote the type of lens fitting in use; it is factory set for CS-mount optics. Once set the back-focus assembly is fixed using a locking screw on the left side of the camera body.

Halfway down the right side of the camera body there’s a standard 4-pin socket for DC-controlled auto iris lenses (a blank plug is supplied with the camera), next to it is the sensitivity adjustment preset, accessed through a hole adjacent to the socket. The top and bottom panels of the casing have threaded holes for the camera mounting bracket. A removable flap on the underside of bracket covers a cable tidy for auto-iris lenses.

On the back panel there’s a set of five screw terminals, three of them are for

video-input type auto iris lenses; the other two are for the power supply connections. Immediately below the terminals there’s a specially designed connector for a service interface plug, and beneath that is a green power-on indicator LED. The composite video output is carried by a BNC socket, located in the middle of the panel. Next to that there’s a pair of recessed presets, for manual white balance adjustment (red/blue bias) and pre-setting the line-lock phase. A 5-way DIP switch in the bottom left hand corner selects auto or manual white balance, AGC on/off, backlight compensation on/off, auto electronic shutter on/off and internal or line-locked synchronisation.

Inside the case there are no less than five printed circuit boards, six if you count a daughter board attached to the power supply module in the base of the camera. The PCBs are bolted to a rigid sub-frame and they connect to one another by short ribbon cables. The main video processing circuitry is on a double-sided board in the top half of the assembly, this contains a high proportion of surface mounted components (SMCs), which contributes to the compact design and should ensure reliability and a high degree of immunity to physical shock. There are no user or installer adjustments inside the case. Quality of construction and attention to detail are  most impressive, it has clearly been built to last.

PERFORMANCE

Installation and alignment are relatively painless. The first task is to fit the lens and, where appropriate, the auto-iris connections. The back focus adjustment takes just a few moments, it has been very well thought out, moreover the instructions are unusually concise and cover all of the most common lens configurations. The preset adjustments and switched options on the back and side of the camera are largely determined by the type of lens used

Using an 8.5mm f1.5 lens resolution our sample came very close to the manufacturer’s figure of 330-lines. Low light sensitivity was also within the specification, though whilst it produces a useable image at very low lighting levels, it can be very grainy, colour fidelity is poor. Moreover, care should be taken to avoid bright lights in the scene area as this can upset the exposure system, even with the backlight compensation engaged. The auto exposure system reacts relatively quickly to changes in lighting level, though an auto iris lens is recommended for installations where there is likely to be a large variation in lighting levels throughout the day. In spite of the various manual exposure options it can still be quite difficult to compensate for the effects of strong lights in the scene.

In good natural light colours are reasonably well defined with minimal smearing and very little noise.  In mixed natural and artificial light colour fidelity can be a little variable and it may be necessary to tweak the white balance control to achieve a satisfactory compromise. Tube lighting can be quite awkward, especially if there are a lot of lot of light coloured surfaces in the scene; it can be difficult to compensate for  a slight greenish-yellow caste in the picture.

OVERALL ASSESSMENT

JVC have largely succeeded in their aims to develop a versatile and cost-effective multi-purpose colour camera. The TK-C600 is small and unobtrusive, it will operate with almost any type of lens and installation should pose no problems in the vast majority of cases. It has a good range of set-up options, though care needs to be taken with the final alignment as the on-board exposure systems are optimised for uncomplicated, evenly-lit scenes.

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 2212