Q: We're fed up with the images we get from our few-year-old surveillance solution - it's fine during the day but as soon as evening arrives we lose the fine detail to noise and blur. We've also installed a higher resolution camera in a key location to get more detail and find at night for the above reasons we get even less detail than before! We also have IT bullets but their performance in monochrome leaves plenty to be desired in the real world. Is there a surveillance camera that gives court-admissible images at 5 lux or is this impossible for current technology? A: Our testing shows that most cameras suffer from noise and blur under 10 lux. We favour noise over blur but there's a law of diminishing returns. You should be able to get court admissible images at 5 lux out to 12 metres at 5-6mm focal lengths. You can increase the minimum shutter speed to reduce blur but the impact on image quality isn't always clear cut. We would be using slightly longer focal lengths with cameras we were depending on at night. If we really needed faces we'd be providing some additional lighting, or leveraging existing ambient lighting.
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