You need a ton of optical zoom to basically have just the vehicle in the field of view.
Keep in mind that this is a
camera dedicated to plates and not an overview camera also. It is as much an art as it is a science.
You will need two cameras. For LPR we need to zoom in tight to make the plate as large as possible. For most of us, all you see is the not much more than a vehicle in the entire frame. Now maybe in the right location during the day it might be able to see some other things, but not at night.
At night, we have to run a very fast shutter speed (1/2,000) and in B/W with IR and the image will be black. All you will see are head/tail lights and the plate. Some people can get away with color if they have enough street lights, but most of us cannot. Here is a representative sample of plates I get at night of vehicles traveling about 45MPH at 175 feet from my 2MP camera (that is all that is needed for plates):
Most of us go with the 5241E-Z12E for this because it has the best focal length. This will work for most people up to around 180 feet with internal infrared. Some have been able to squeeze more to about 220 feet with external infrared.
If your distance from plate to camera is less than 60 feet, you could go with the 5442-Z4E and if within 30 feet you could go with a cheaper 2MP varifocal.
Keep in mind the above-referenced cameras do not actually read the plates. They are set up to allow you to manually visually read them. You can use a 3rd party tool to actually read and log the plates if that is what you want.
The true LPR cameras that read plates would not have enough zoom. They would max out around 60-ish feet or so.
Take a look at the LPR subforum for more:
Licence Plate Reader cameras
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