I was comparing specs of a couple of Dahua cameras and noticed many of their 2MP and 4MP cameras have the same sensor/size, same F-stop, but also have the same minimum illumination numbers. I don't understand how this is possible. If the optics are the same, the CMOS's type/physical size is the same, and you divide the individual pixel size down, it should have less sensitivity. Can anyone explain what's going on here?