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Frequently Asked Question

1. Will the Camera's work anywhere in the World?
The output of CCTV cameras is composite video. U.S, Japan and Canada uses NTSC system whereas most Asia and European countries uses PAL system.

2. What is NTSC and PAL system?
NTSC stands for National Television Standards Committee. It is the colour video signal television standard: 525 lines, 60Hz
PAL stands for Phase Alternate Line. It is the colour video signal television standard: 625 lines, 50Hz

3. How does focal length affect angle of view?
Focal length is measured in mm. A short focal length (e.g. 3.6mm) represents a wide angle of view while a long focal length (16mm) represents a narrow angle of view.

4. What is Day and Night Camera?
Day and night cameras are cameras that are able to provide video surveillance even at low levels of illumination. A day and night camera displays a full colour image during the daytime but produces monochrome (Black and white) video images at times when the lighting is poor.

The camera has a device that is sensitive to the surrounding light conditions and switches the camera between colour and black & white modes automatically. It is designed to increase its light sensitivity in poor lighting conditions and at the same time reduce noise level in the images. However, the day and night camera will fail if the illumination (Lux) level is too low.

5. What is C and CS mounts?
It refers to the 2 different standards of CCTV camera lens mount. The difference between the two is the distance between the lens and the image sensor. C mount: 17.5mm, CS mount: 12.5mm. Cameras and lenses nowadays are generally CS mount rather than C mount.

With CS mount cameras, both types of lenses can be used. However, the C mount lens requires an additional 5mm ring to be fitted between the camera and lens to achieve a focused image. With C mount cameras it is not possible to use CS mount lenses as it is not physically possible to mount the lens close enough to the image sense to achieve a focused image.

6. What is the difference between a PC-based DVR and an Embedded DVR?
A PC-based digital video recorder is basically a personal computer that has been modified with hardware and software to work as a DVR. An embedded digital video recorder is a video recording machine that has been manufactured specifically to record video input from CCTV cameras. In embedded DVRs there is typically one circuit board with software burned into its processor chip.

There used to be significant differences in features between the PC-based and the embedded machines. But with recent advancements in the embedded DVR technologies the differences are becoming less. The advantage of an embedded digital video recorder is that they are extremely stable and reliable as they consist of fewer circuitry parts. The software is often written in basic machine code or Linux code which tends to be more stable.

The advantages of the PC-based digital video recorders is that they are easier to interact with because you use the on-screen menus and a mouse (as opposed to embedded which you interact with more like a VCR - via buttons). And you tend to have more features and options on the PC-based machines.

7. What is the difference between a simplex DVR and a duplex DVR?
A simplex DVR only performs one task at a time. The DVR cannot playback recorded videos when it is recording, it can only do so when the recording is stopped.

A duplex DVR is able to playback recorded footages without having to stop recording. Recording is uninterrupted and taking place concurrently as you playback the recorded videos.