AES - Automatic Electronic Shutter Explained
Cameras need to be able to measure the present scene illumination, in order to determine the overall video brightness. In modern day the most advanced and commonly used method is Auto-Iris. Auto-Iris is established through team-work of a professional CCTV CCD Camera in conjunction with a modern lens - both supporting Auto Iris function. The camera measures the light level - decides whether it needs more or less light - and then adjusts the motorised iris in the Auto Iris Lens (open further or close), via a small control cable.
The most common cause for not equipping cameras with auto iris lenses is the cost-saving factor. Utilising AES, a standard Manual Iris Lens will be used on an average setting (determined by needed and average scene illumination. The electronic in the camera will modify the shutter speed of the CCD Chip. Increase in shuttering = darker image, decrease of shutter speed = brighter image.
Adavantage = Cost Saving. Disadvantage = less crisp image quality and less quality when capturing moving objects.
Engineer Tip: Be sure to TURN OFF AES whn an Auto Iris is being used.