The bench test 1: Seeing the Lite

There is something a little disconcerting about really small PTZ dome cameras. The delicate toy-like mechanisms simply do not look robust enough to withstand the rigours of 24/7 operation. That shouldn't be an issue with this mini dome, though, and Norbain has subjected the Vista VPD4 PowerDome Lite to a series of gruelling HALT (Highly Accelerated Life Testing) checks, which included running it in temperatures of between -60 to +90 degrees centigrade, which is well outside of its specified operating range of -10 to +40 degrees C.

Needless to say it passed with flying colours. It is IP66 rated for indoor and outside installations and the 'Vandal Resistant' tag line after the model number indicates that it is designed to function in physically demanding environments.

In spite of its impressive-sounding credentials the VPD4 is far from a specialist product; it is being pitched as a cost-effective surveillance solution and Vista's target market is a broad one and includes retail outlets, schools, hospitals, hotels, airports, leisure facilities and car parks.

It is genuinely small, measuring just 145 x 117mm (the transparent dome is 99mm across) without any of its many and various mounting options, yet this small package packs quite a punch. The colour camera module is based around a ¼-inch Sony Super HAD image sensor with a 752 x 582 pixel matrix. This delivers a claimed resolution of more than 430 lines with a low light sensitivity down to 1.5 lux. It has a built-in 10x optical zoom lens with switchable 10x electronic zoom and a full set of manual and automatic exposure and white balance options.

The pan/tilt mechanism is remarkably nimble and for the record it can pan through 359 degrees and tilts from 0 to 90 degrees, in both cases at up to 120 deg/sec. An auto flip mode spins the camera when it points directly downwards so it can follow moving targets as they pass underneath the lens.

The VPD4 can store up to 60 preset positions and follow four tours, each of up to 16 presets. Additionally it has Auto Scan and one programmable alarm input. Keyboard control and communications is handled by a RS485 transceiver (Vista or Pelco D protocols). It can also be controlled by other devices through the video connection using N-FSK. Power requirements are 12VDC or 24VAC and it can be fitted with an optional heater module inside the dome housing.

Time for a look inside, and the top two sections of the three-part housing are made from cast alloy. The clear polycarbonate dome is attached to the inside of the centre section so it cannot be removed or interfered with and tamper-resistant security bolts hold the two body sections together.

There is one PCB with a daughter board inside the case (apart from the circuit boards that make up the camera module) and this is responsible for power supply, motor control and telemetry functions, as well as providing mounting points for the pan mechanism.

The camera module is mounted inside a simple U-bracket and moved by a twin belt-drive reduction gear system coupled to a miniature stepper motor. A similar dual belt drive arrangement is used to rotate the camera platform.

A small temperature-controlled fan is fitted to the rear of the camera module and initially we thought this was responsible for the constant 'hissing' sound coming from the mechanism. However, this turned out to be the pan motor, which emitted various different types of hiss and whining sounds, even when stationary, depending where it was on its travel.

All connection to the outside word is carried on a single 8-way socket on the underside of the main PCB. Access is through a weatherproof access hatch on the top of the case.

Setup and operation

The only time the dome and bottom cover needs to be removed is to set the camera's protocol and ID Address. In both cases these parameters are set using a microscopic DIP switch on the main PCB. Otherwise all other functions are controlled from a set of on-screen displays. For the purposes of our test we used the VPD4 with a Vista NPX KBD/H3De keyboard, routing telemetry and power connections through a BAXKMI Network Access Point junction box.

It all sounds fairly straightforward but getting the two units to communicate proved to be something of a headache. Despite being marketed by the same company the accompanying instructions are singularly unhelpful when it comes to connecting them together. The first problem is the RS485 connection, which on the camera are labelled '485+' and '485 -'. The junction box also has 485+ and - connections on a screw terminal, however delve into the instructions and it transpires these are not used and should be disabled by moving small jumper links. Instead it is necessary to use terminals marked Rx and Tx.

It also takes a while to realise that the controller needs to be reconfigured, to disable Baxnet protocol and change the baud rate, and this time the instructions are downright misleading, implying that this can be done in one action from the configuration menu. Suffice it to say it took a lot longer than it should have done to get it working.

Once it is up and running the main menu is accessed by pressing and holding the 'dome' key on the controller and entering a password. The latter is easier said than done - instead of following logic and tapping it in on the controller's numeric keyboard, the PIN has top be laboriously entered one digit at a time by twisting the zoom knob on the joystick.

There are six options on the main menu: Preset, Tour, Auto Scan, Alarm, Camera Setup and Dome Setup. The Preset menu is by no means intuitive, though it becomes easier with practice. Each preset can be individually assigned a title; this also relies on wiggling the joystick to change characters, a slow and torturous business, which is worth bearing in mind if you plan to set up more than a dozen presets.

The position is set by moving the joystick and stored by the pressing the Escape key. Fortunately the Tour and Auto Scan menus are a little more straightforward but again there is the option to set a title.

On the Alarm menu there are options to enable or disable the facility, enter the preset number the camera will move to if the alarm is activated and the dwell time, which is from 5 to 99 seconds.

The Camera Setup menu should have been split into several sections as it covers a great many diverse functions. The sub-menu options are Focus Control (auto/manual, near focus distance, digital zoom), White Balance Control (Auto/Manual, red and blue gain), AE Control (shutter/iris priority, iris - F1.8 - F22 & close, gain, shutter 1/100 - 1/10000 sec, brightness level and Backlight Compensation), B/W Control (colour /mono switching), Line Lock Control (internal/external, phase adjustment), Lens Control (optical zoom setting) and Initialise Camera (reset to factory defaults).

Last but not least the Dome Setup menus, which has switches for the on-screen display, tilt auto-flip, password setup, initialise domes (reset all settings to factory defaults) and Dome Information (firmware version etc.) Fortunately the dome should only need configuring once, which is just as well as the design of the menus and the keyboard controller turns what should be a relatively simple procedure into a time consuming chore.

Performance

Almost all the camera's foibles can be forgiven when you see the quality of the video. The manufacturer's specs are a little vague on the subject of resolution; the instruction manual claims 430 lines whilst the Norbain website mentions 480 lines and we judge it to lie somewhere in between, but the fact is, in good natural light the image is sharp, vibrant and very clean. Colour fidelity is excellent and the auto WB system managed to maintain a high level of accuracy in both mixed and artificial light. Auto exposure control is similarly dependable in most conditions and the backlight control deserves a special mention for its ability to deal quickly and effectively with both large and small bright lights in the image area.

The autofocus system is fast and responsive and works surprisingly well in poor light, though inevitably as contrast levels fall it becomes necessary to assume manual control.The transparent dome creates the odd internal reflection but they are fewer and much less intrusive than most of the dome cameras we've looked at recently.

Pan and Tilt actions are smooth with negligible under or overshoot when rapidly moving between preset positions. The small size and low mass of the camera module and the PT mechanism obviously contribute to its agility, and stability and nothing short of a hammer blow is going to make the picture budge - certainly the Bench Test rubber mallet test had no effect on it.

What the manufacturer says ...

The PowerDome Lite VPD4 has been specifically designed to combine many of the high performance features of a fully functional dome camera at a genuinely cost effective price.

The vandal resistant, miniature high-speed dome is just 145 x 117.2mm in size, whilst still offering a 10:1 optical zoom, allowing the operator to move in for closer inspection where required. Four tours are available, each with 16 presets, multi-protocol compatibility and an impressive resolution of 480TVL.

Application and installation options haven't been compromised as the VPD4 is rated to IP66 for internal or external installation, which guarantees fully functional operation at temperatures between -10degC and +40degC.

The domes are compatible with all existing PowerDome bracketry so that there is always a mounting solution to fit the application. Additionally, the VPD4 is compatible with Vista and Pelco D telemetry control protocols via twisted pair (RS485) or Vista (FSK) protocols on coaxial cables, the latter enabling one cable to be used for both telemetry and video. This makes it an ideal solution for retro-fit installations where the customer wants to replace static cameras. Further flexibility of application is achieved due to the VPD4s compatibility with Vista's extensive range of PowerDomes, Triplex DVRs and Smart Transmission products as well as Vista's award winning 360 deg eclipse camera range.

The VPD4 is suited to a vast range of markets where there is a need for cost effective surveillance, without a compromise in quality. These markets include retail outlets, hospitals, schools, car parks, hotels, airports, and leisure facilities.