It's a set up!

You could say that fixed domes are the Cinderellas of the surveillance camera market. They lack the glitz and impressive agility of PTZ cameras, and unlike regular fixed cameras, there's little or no scope for fancy lenses or interesting cosmetics. Nevertheless, it's a tough job, someone has got to do it – and who better than Sanyo?

The fact that the VDC-P7575PA is made by Sanyo is just about the only thing you can tell about it from the outside, but as you delve deeper it quickly becomes obvious that this camera is a lot cleverer than your average run of the mill compact dome.

For example, it has a motorised 2.6x optical zoom lens – not something you see every day – but there's more. The zoom can be linked to the camera's motion sensor and programmed to zoom in, hopefully to better see what set it off. At least that's the theory – more on that in a moment – but right now we're getting ahead of ourselves, so we'll take a step back with a brief look at the camera's specs.

The image sensor is a ¼-inch interline CCD with a 752 x 582 pixel matrix, giving a claimed 520 lines of resolution and a low light sensitivity of 1.9 lux in gain up mode. Sanyo hasn't bucked the current tend for day/night operation, and while it's not fitted to this particular model others in the range do have this facility, though it's difficult to see how they managed to shoehorn it on the overcrowded camera/lens module.

Exposure options include two-mode backlight compensation (multi-spot/centre-zone metering), multi-mode while balance, two-stage gain control, aperture compensation, switchable gamma correction and an electronic shutter. In addition to the motion sensor it also has a 16-character camera title display, four-zone privacy mask, alarm input and internal or line-lock sync.

The camera mount can be rotated through 330 degrees and tilted through 90 degrees. There is also provision to wall mount the camera, by rotating it on its bracket, after which it can pan from side to side through a full 180 degrees.

Externally there's little to differentiate this camera from most other domes on the market, but the devil is in the detail, and Sanyo has worked hard to speed up wiring and installation. A simple detachable base plate, released by a button on the side, has a set of spring terminals for the power supply (12 volt DC or 24 volts AC), plus a second connector block for the alarm, remote comms (for other models in the range) and remote control connections for the zoom lens. The video output is on a short captive cable, terminated with a BNC line socket.

Unusually for a dome camera access to the innards is quick and simple; just pop a latch, give the lower case a twist and off it comes. The two parts are connected together by an anti-drop tether. The camera module sits in a simple three-axis mount with friction bearings. This means there's no need to slacken off any locking screws, just move the camera to where you want it to be and there it stays.

The camera is attached to a metal chassis fixed to the inside of the top part of the case, and this also supports the single PCB which is responsible for the power supply, comms and control functions. It has a menu-driven on-screen display, and selections and changes to settings are made using a button and a tiny four-way 'cursor' switch on one edge of the circuit board.

Build quality is generally good; the case is all plastic, which helps keep the all up weight down to 0.6kg. With the cover removed it's a little untidy, with straggly looking wire and ribbon cables connecting the main board to the camera module. One set of cables appears to be completely redundant and restrained by a clip on the side of the case. Presumably they are for ancillary functions (heater, microphone etc), which are available as options or as standard on other models in the range. The two parts of the case are connected together by an anti-drop tether and a black shroud inside the dome helps hide the lens and reduce reflections from inside the dome.

Setup and operation

Sanyo's VDC-P7575PA compact fixed dome camera is easy to install, but could be vulnerable to attack...

Using the on-board control buttons to access the camera's setup menu seems like a good idea at first but in practice, teetering on top of a ladder, trying to glimpse a distant monitor (or juggling with a hand-held), could be a bit if a challenge.

Sanyo has it covered, and for those who need to set up more than one or two of these cameras a hand-held remote keypad (VAC-70) is available that connects to the video feed cable. The options are the same in both cases and the right and left cursor buttons are used to adjust the zoom. Pressing the Menu button on the remote, or holding down the Set button on the PCB, brings up the opening page of the on-screen menu and this has ten switched functions.

From top to bottom they are: Sync (internal/external), Backlight Control (off, multi-spot high or low and centre zone), Iris (variable level), White Balance (manual, ATW, ATC, 3200, 5600, fluorescent), AGC Gain (off, normal & high), Gamma (0.45 or 1), Shutter (1/50 - 1/10,000 sec in 8 steps) Aperture (off, normal, high & high plus) and Option.

The Option menu leads to a set of sub-menus for composing and positioning the camera title, setting up the privacy masks, setting the alarm (alarm input relay, motion sensor targets, sensitivity, alarm-activated zoom settings and the alarm signal), setting up a password to protect the menus and changing the menu language (English, French or German).

It's all fairly intuitive and most of the menus are reasonably easy to navigate. The only slightly tricky areas are the motion detector and privacy mask settings. The former might require some fiddling with the camera position, as the target grid is a widely spaced matrix of 16 small blocks. If the area of interest is quite small the camera might need to be re-positioned. The privacy mask suffers from a similar problem, this time because the masks blocks are so large and care needs to be taken not to blot out too much of the image.

Performance

In spite of the camera's fairly average low light characteristics it manages to produce a crisp, clean image over a very wide range of lighting conditions. In good light, resolution on our sample came reasonably close to the manufacturer's figure; noise levels are normally low but grain does increase quite quickly as light levels fall. The AGC kicks in quite abruptly too, almost like a day/night function, resulting in a sudden switch to a near monochrome image.

The exposure system is a little coarse and sudden changes in light level produce slight pulsations, though to be fair this would not be noticeable in normal use with gradual changes of illumination. With the white balance under auto control colour accuracy is very good and it handles mixed lighting without any problems; in any event there's always the safety net of the manual controls and presets for really difficult situations.

Mechanical stability is excellent and the image didn't flinch when the dome was treated to a few taps from the SI rubber mallet. Overall build quality is fine, a tad light and thin in places but it looks as though it should be able to withstand normal wear and tear.

We do have one small concern, however, and that is the ease with which it can be removed from its mount and how simple it is to detach the dome and lower caser.

It is most definitely not a vandal proof or even vandal resistant design and this should be borne in mind when it comes to its location, which should be well out of reach.