This is normally accomplished with a simple plug-in connection to the camera's back or side. However, you should always consult the camera's manual.

The aperture of the lens adjusts automatically in reaction to light levels with an Auto-Iris mechanism. The programme starts the process by regulating a drive connected to the Iris, which is then adjusted to open or close the aperture as needed.

An auto-iris lens regulates and optimises the quantity of light or infrared radiation received by a camera by automatically adjusting the iris (or aperture). This is suitable for outdoor video surveillance cameras, which are frequently exposed to shifting light conditions and high-contrast environments

The iris is a physical opening incorporated into a lens operated by a small servo motor, and it is frequently used in conjunction with DSP image processing such as WDR, HLC, and BLC. It enables security and surveillance cameras to modify and optimise images on the fly in response to changing lighting conditions.

Read More: When can you use a manual iris lens?