Day Cameras
There are two types of camera for daylight use: those with irises and those without. The iris controls the amount of light reaching the image recording area at the rear of the camera. Without an iris the cameras can only be used internally: a 'white out' occurs in sunlight when the camera cannot cope with the intensity of the light reaching it: this can also cause damage the sensitive parts. If you have experience of webcams, you may have seen this effect in practice.

It is possible, but not recommended, that internal cameras without irises (the 207, 207W and 207MW) can be fixed to see through shaded windows and pointed downwards so that the sky cannot be seen, thus avoiding overexposure.

Cameras with controllable irises are significantly more expensive (211A, 221) but can be used in and out of doors. The iris is automatically adjusted to the optimum for the camera as the lighting changes.

All these cameras will record at night if a light is left on illuminating the scene (even a streetlight will do), but the colours, quality and number of images per second will not be as good as in better lighting conditions. This is demonstrated in the demo events under different lighting conditions.

Day/Night and Infra Red camera: the Axis 221
The 221 is more expensive than the other daylight cameras, but it has both day/night and infra red modes to record much better images in low light conditions. It will switch to black and white in low light and reduce the number of images per second. It can also be used in total darkness with an infra red light to record black and white images: a recording of a genuine burglary is shown in the demo section. The infra red light given out by the lamp is invisible to the naked eye, and looking into the lamp itself only shows a faint red glow. This is an expensive solution and is only required in complete darkness. If there is another light source, such as a streetlight, then the infra red effect will be swamped by the other light.

Axis 211A Internal or external camera with an iris to control light flow to the sensor More info	Axis 221 Infra red camera capable of working in very low light More info

<Back