How Well do IP Cameras Work in Low Light?

JH
John Honovich
•Published Jun 06, 2009 04:00 AM

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Determine *** ******'* **********

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Tradeoffs ** ***-***** *************

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  • Black *** ***** ****: Cameras provide better low light quality when switched to B&W mode. This is accomplished by the use of a mechanical cut filter and are usually labeled as being Day/Night cameras. [Note: a few cameras provide 2 imagers - one B&W and another for color]. This is the one feature that works the best with the least tradeoffs. Black and white mode almost always provides a substantial better image than the color mode at the same light level. The obvious tradeoff is capturing color.
  • Slowing ******* *****/ *********** ********: If there's very little light, one way to get more light is to take a longer time to capture the image. Instead of using a 1/30 second exposure, it could be lengthed to 1/5 second or even 1/2 second. The two significant drawbacks of this is: (1) reduces frame rate and (2) causes issues with motion blur. If a car or person is moving quickly across the camera, the long exposure can distort details - rendering the image potentially useless. Manufacturers obscure this problem by showing still images of stationary objects.
  • Increasing **** / ********* ******: Manufacturers can artificially enhance images to increase details in the image. The problem is that these techniques routinely introduce noise (e.g., the appearance of 'snow' or lines in the image). These artifacts can create new problems, especially if you are attempting to see fine details or perform video analytics. In our videos below, these issues can be seen very clearly.

Analyzing ***** *******

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Download ***** *******

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