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One look at the thickness of the instruction manuals supplied with many recent video cameras shows just how far and how fast the technology has progressed in the past few years... Not so long ago everything an installer needed to know, to get a camera up and running, could be printed on one side of a sheet of paper.


The instruction book accompanying the JVC TK-C1380 colour camera runs to some 55 pages, though to be fair only 18 of them are in English. Nevertheless it contains a great deal of important information, much of it concerned with this camera’s extensive array of user-adjustments, exposure facilities and convenience features.


From the outside the TK-C1380 looks conventional enough. It’s housed in a cream-coloured rectangular section steel case, measuring 159 x 70 x 69mm. At the front there’s a C/CS threaded mounting collar, that also performs back-focus adjustment via a discrete thumbwheel protruding through the front end plate. Behind the lens there’s a 0.5-inch interline-transfer CCD image sensor. It has a total of 470,000 pixels, of which 440,000 are effective (752 x 582 matrix), giving a stated resolution of 470 lines and a low light sensitivity of 0.95 lux.


The case is fitted with a detachable mounting plate, that can be bolted to the top or bottom of the camera; it has two 1/4-inch threaded mounting bosses, to suit a variety of mounting hardware, housings and lens configurations. On the left side of the camera body, close to the front, is a back-focus locking screw; on the right side is a standard 4-pin DC iris connector socket.  The back panel has two BNC sockets, for the composite video output and external synchronisation. An S-Video (Y/C) output is provided by a 6-pin mini DIN socket. There are two screw terminal blocks, the upper one is for video-controlled auto-iris connections, the lower one for the power supply, which can be either 12 volts DC, or 24 volts AC 50/60Hz. A second variant of this camera (TC-C1381) is also available, which has a built-in AC mains power supply.


Inside the camera there are half a dozen densely packed PCBs, attached to a metal chassis. The CCD module at the front, and control panel at the back are easily detachable, though there’s little scope for servicing, not that it should require a lot of attention. The PCBs are almost entirely populated by surface mount components (SMCs), which have an excellent track-record for ruggedness and reliability. The electronics generate a fair amount of heat and the camera gets quite warm in normal operation. There are no ventilation holes or slots as such, and the case isn’t weather-proofed, so some sort of protective housing will be required, if the camera is to be used in a damp, dusty or otherwise hostile environment.



In the centre of the back panel there’s a group of five miniature push-buttons, which control all of the camera’s configuration and user pre-set functions. They’re shown via a series of menu-controlled on-screen displays, superimposed on the video output. Pressing the centre ‘set’ button once calls up the first menu. This has four options: Synch Adjust, Video Adjust, Mode Select and End/Memory. Each item on the menu is linked to a series of further menu displays. Sync Adjust has the following selections: ‘term’ (75 ohm or open termination on the video output),  ‘H-Phase’ (horizontal adjustment for gen-lock operation), ‘SC Coarse’ & ‘SC Fine’ (sub-carrier phase adjustment for gen-lock operation), ‘Line Lock’ (adjustment of vertical synch to AC frequency), ‘V-Coarse’ & ‘V-Fine’ (vertical phase adjustment for line-lock mode).


The Video Adjust menu has five settings: iris, colour, pedestal, enhancement and hue, which can all be adjusted either side of a nominal zero default value in plus or minus five steps. The Mode Select menu covers some of the camera’s more exotic features. They include enabling and setting the camera ID, AGC gain control, Super AGC, high-speed shutter, backlight control, average value/peak value exposure detection, white balance adjustment and highlight inverter. We’ll look at them in more detail in just a moment.


All menu operations are very straightforward, the item to be selected is identified with a moving cursor, using the up/down buttons, then the value or setting is changed using the right/left or set buttons. The only small point to bear in mind is that most of the camera adjustments will have to be carried out in-situ, so the controls need to be accessible, and a colour monitor will be required at the installation point.


Creating a camera ident is one of the jobs that can be done off-site. It only takes a few minutes; the display can accommodate one line of up to 24 characters. In the edit mode the full character set of upper and lower case letter, numbers and basic punctuation marks is displayed on the screen. The ident, which is in a fixed location at the bottom of the screen,  has to be built up one character at a time. It wouldn’t be quite so slow to use if the character selecting cursor didn’t return to the end of the character set after each selection.


The AGC control has three settings, 0, 9 and 18dB; if the maximum sensitivity setting is insufficient the Super AGC mode gives an extra stage of gain, though this can be at the expense of increased picture noise on poorly illuminated scenes.  The electronic shutter has automatic and manual operating modes; there are 8 manual speeds (1/50, 1/120, 1/250, 1/500, 1/1000, 1/2000, 1,4000 and 1/10,000 th second. On the auto setting shutter speed will vary between 1/50th to 1/10,000th second, or it can be fixed at 1/50th.


Backlight compensation is very flexible, it can be set to operate using four pre-defined areas of the picture, or customised by the user/installer. The size and position of the detecting area can be changed using the four cursor buttons, which move four blue-coloured ‘screens’ that emerge from each side of the display. Average and Peak value exposure detection is used when the camera is fitted with an auto iris. The average/peak value setting is effectively a ratio, that defines how the exposure detection system reacts to lighting changes. Increasing the influence of average value metering helps when the picture looks washed out, as can happen on a dark scene, illuminated by artificial light. The effect of peak value metering is to reduce halation on picture highlights. The range of adjustment, i.e. the ratio of average to peak value metering is in 6 steps (5:5, 6:4, 7:3, 8:2, 9:1, 10:1) with the factory default set at 8:2.


White balance control can be either manual or automatic, in the manual mode the display enables adjustment to red/blue and green/magenta values.  The Highlight Inverter feature is used to improve image detail close to brightly lit areas in the picture. When it is enabled those areas of the picture, that exceed one of three preset brightness values, are inverted, so they appear black.



We tested our sample with a variety of lenses, with manual and auto iris functions, all of which performed satisfactorily. The first parameter we checked was low-light sensitivity, and we’re pleased to report the manufacturer’s quoted figure of 0.95 lux -- with the AGC wound right up -- was about right. Under these conditions -- i.e. little incident light -- there is still plenty of detail, though colours are muted, and the image looks quite grainy.


In typical lighting conditions -- from 1000 to 10,000 lux -- definition is good and our sample was able to resolve more than 450-lines. The enhance adjustment marginally increases edge definition, though in the end we left our test camera on the ‘0’ default  setting, otherwise the picture ended up looking harsh and gritty. Colour fidelity in the auto mode is very respectable and it copes well with most forms of artificial lighting. Where lighting conditions remain fairly static it’s worth fine-tuning the response using the manual settings, which can compensate for quite serious aberrations.


The exposure options are most impressive, though a lot will also depend on the type of lens and iris used with the camera. The range of iris control is sufficient to deal with most situations, DC and video controlled auto-iris functions are fast and responsive, with minimal overshoot.



The TK-C1380 is a real Jack of all trades, without any of the usual drawbacks; it’s good at just about everything it does. Performance, flexibility and versatility are all there, in equal measure. Low light sensitivity and the huge range of exposure options single this camera out for demanding applications, where non-specialist or less well specified models simply can’t cope.



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 1996 2511











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