Actually, I am researching them right now as well. I was looking at something like this:
Swann
I have read that the CCD optical sensor is better quality than the cheaper CMOS sensors. I have nothing to back that up, though, other than a quick search an comments.
A friend of mine had a number of break-ins in his neighborhood two nights ago. He had a surveillance system and was able to get video of a teenage kid walking up to his front door, looking into the windows, then walking off at 3am. The IR video worked great. He posted the video for the HOA. A suspect was being questioned hours later.
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