Panasonic WV-NP472

Despite offering an extensive range of analog surveillance cameras, electronics giant Panasonic only moved into the network camera market late in 2003 and currently offers four products. Three of these are ceiling and wall-mounted PTZ (pan, tilt, zoom) models, while the WV-NP472 is a static colour camera aimed specifically at 24-hour surveillance. Unique among network cameras, the body is designed to accept a variety of lenses, and Panasonic offers options for high-speed, powered remote zoom, auto-iris and auto-focus functions.

Another key feature is the camera's ability to function in very low light levels, as it can automatically drop down to a mono image as soon as the light levels go below 0.8 lux. We tested the camera in several lighting scenarios and found that it could indeed function with little available light, such as a street lamp or a security light. We could even see detail in a room lit only by the glow from the test laptop's screen.

Installation is simply a case of pointing a browser at the camera's default IP address, but although the image quality is good we weren't impressed with the delivery method. The camera updates the web page at each refresh interval, resulting in a constantly flashing cursor, and we also had to deselect IE's status bar as this displayed a message at every update. Panasonic doesn't quote a frame rate, but we estimated the Fast refresh mode was updating the image at around six times per second.

The camera offers an extensive range of features and settings, and access to these is via a menu system overlaid on the image. This can be managed from the browser interface, but sliding back a small panel on the side of the camera reveals manual control buttons for local access. Setting up the motion-detection feature is simple and it can be customised to suit different environments. A contact block can also be used to wire in sensors, plus alarms can trigger automatic image downloads to an FTP server; these images can also be emailed to one address.

One problem that network administrators frequently quote as a reason not to implement network cameras is excessive bandwidth usage, so to test this we used Network Associates Sniffer analysis software. On a hub-based 100Base-T Ethernet network with one client accessing the camera we saw about 3 per cent utilisation, which increased to no more than 5 per cent with two clients. Dropping the refresh rate from Fast to Slow reduced this to less than 2 per cent with two clients.

We also tested the camera using the analog feed to an Axis 2411 Video Server (see issue 113, p174), which didn't reduce bandwidth usage but delivered some marked improvement for the video feed. Picture quality was marginally clearer, but the update rate was sufficiently improved to allow far smoother movement to be relayed in the image. We also didn't get the annoying download messages in IE or the constant mouse twitches indicating background activity.

The biggest strength of this camera is its ability to function in very low light levels, which makes it a far better bet for round-the-clock surveillance than budget-priced network cameras. The option to use different lens types is a bonus, although the best video feed came from using an analog connection.

Author: Dave Mitchell