As already suggested, read here> LPR | IP Cam TalkActually getting them to focus at night is easy. there are a couple of different ways to do it.
Again, how far from the camera to the license plate? It makes a difference....without that nobody can tell you what camera
We're talking apples and oranges here....pick one
(change youtube player to 1080p)
Overview camera (sees a lot of area but little detail further out)
LPR camera (sees fine detail but small field of view)