I use the IPC-HFW5231E-Z12E for my LPR cam. Here's an example of my captures:
- Vertical camera height - 11 feet
- Horizontal angle - nearly straight on (maybe 5 degrees)
- Distance from target area - 102 feet
- Zoom - full zoom (64mm)
I also use the DahuaSunriseSunset utility that
@bp2008 created to change between day and night profiles.
My night shots biggest enemy is mist/fog (weather related) which I seem to get on occasion - can see a bit in the shot I posted below.
@bigredfish made a great suggestion for me to bump up my contrast and set a fixed shutter speed at night and that has helped even more - see bottom shot with adjusted night settings.
Note: I may not have any exact reason for my settings below, I just tweaked them all after reading many posts here and on other sites. They seem to be ok for me so that's why I've stuck with what you see below. I can't really explain "why" I've chosen some of the settings below.
I'm only trying to get a good image at a target spot of 102 feet away - I parked my car at that spot in the day and at night to adjust the focus - so I have my iris set quite open at 90 because of don't care about a narrow DOF. That way I can maximize the light coming into the lens. My understanding is that a small iris setting gives a wide DOF (good focus near and far) and a large/wide iris gives a very shallow DOF.
Adjusted night settings from @bigredfish suggestions of contrast increase and fixed shutter setting, also went to 1/1000 vs 1/500 (1ms vs 2ms):