How commonly do you contend with video flickering due to fluorescent light fixture flickering?
The problem often looks similar to this:
Many IP cameras include an exposure setting that inhibits the tight synchronization of camera imager sensor line scanning and the native electrical distribution of AC frequency, ie:
- 50 Hz: Common to Europe and most of Asia
- 60 Hz: Common to North America
The actual frequency of the flickering occurs at 100 or 120 Hz, as the cyclic change of AC current affects the output intensity of the lamp and is much faster than the human eye can see. However, given the fast scanning rate of the imager can sometimes be seen with surveillance cameras if the exposure point matches the wrong frequency.
Many cameras include a 'flicker-free' setting that breaks the synchronization of exposures by a tiny bit (a half cycle), and this cures the issue.
However, with that said, how often do you use it? Is flickering a common problem?
