That camera would be horrible if you do not have any light. This is a full color camera that does not see infrared, so if you do not have enough light, which it sounds like you do not since you said flood lights are not an option, then you are better off with the 5442 series that has infrared capabilities.
Any full color type camera needs light, simple physics. If there are not street lights or floodlights, you need a camera with infrared.
Best focal length is based on the distance you are trying to get a clean capture.
Here are my general distance recommendations, but switch out the Dahua 5442 series camera to the equivalent 2MP on the 1/2.8" sensor or equivalent Hikvision works as well.
- 5442 fixed lens 2.8mm - anything within 10 feet of camera OR as an overview camera
- 5442 ZE - varifocal - distances up to 40-50 feet (personally I wouldn't go past the 30 foot range but I like things closer)
- 5442 Z4E - anything up to 80-100 feet (personally I wouldn't go past 60 feet but I like things closer)
- 5241-Z12E - anything from 80 feet to almost 200 feet (personally I wouldn't go past 150 feet because I like things closer)
- 5241-Z12E - for a license plate cam that you would angle up the street to get plates up to about 175 feet away, or up to 220 with additional IR.
- 49225 PTZ - great PTZ and in conjunction with an NVR or Blue Iris and the cameras above that you can use as spotter cams to point the PTZ to the correct location to compliment the fixed cams.
You need to get the correct camera for the area trying to be covered. A wide angle 2.8mm to IDENTIFY someone 40 feet away is the wrong camera regardless of how good the camera is. A 2.8mm camera to IDENTIFY someone within 10 feet is a good choice OR it is an overview camera to see something happened but not be able to identify who.
One camera cannot be the be all, see all. Each one is selected for covering a specific area. Most of us here have different brands and types, from fixed cams, to varifocals, to PTZs, each one selected for it's primary purpose and to utilize the strength of that particular camera.
The new 4K/X is an incredible full color camera that recently hit the market and is probably one of the best out there, but even it needs light.