normel 0 Posted March 26, 2014 Hello All. We want to buy some nvr together with the ip cameras, but need some advise, what options to pay attention for? I had one at my work, and have some experience with it. 2 big problems we were facing: At dark, the licence plates, and also human faces were becoming white and too highlighted. And even in daylight, fast passing cars licence plates were not readable because of the FPS. So what are the options in the nvr i should take care of ? and what about the camera? Share this post Link to post Share on other sites
drocer 0 Posted March 26, 2014 It's impossible to know what you consider "unacceptable" without a baseline. What FPS is not acceptable? What cameras were you using? Distance the IR had to go? External IR used also? You could have 640x480 crap at your work or 20MP Axis cameras. You can get 2.1MP/3MP IP cameras that can do 30/15fps respectively. As long as it isn't pitch black you can get 30M IR distance. Bullets, domes, and turrets for ~$120-$200. Share this post Link to post Share on other sites
myiicu 0 Posted March 27, 2014 If you want to capture plates consistently and reliably in day or night, use a Bosch LPR camera. They have been in the LPR business for years. These are analog cameras, so a separate encoder is required for IP connection. Bosch REG-X-816-XE approx. $600 http://resource.boschsecurity.com/docum ... 568587.pdf Bosch VLR-4075-V521 approx. $500 http://resource.boschsecurity.com/docum ... 030539.pdf A choking point is required to slow the vehicle to 50mph or less. The LPR camera should be mounted no more than 5 feet above the ground (lower the better), face the licence plate directly, and be around 20 feet away. You will also still require a separate colour overview camera to capture other details such as make, model, color etc. Share this post Link to post Share on other sites
myiicu 0 Posted March 27, 2014 Bright faces too highlighted at night time is usually caused by over exposure due to IR leds being too direct. Use separate IR led lighting to reduce the hot spots or source camera that has "smart" ir leds or "adaptive" ir leds. http://avigilon.com/white-papers/adaptive-ir/ Share this post Link to post Share on other sites
buellwinkle 0 Posted March 27, 2014 First, what's your budget? To read plates at night you need a dedicated camera no matter what. If you want to use something like a bullet or dome to read plates, it will have no other use at night. Get the longest lens you can get, 12mm is bare minimum to read a plate 20-25' at night. Set the max shutter speed to about 100-250/second. This will make the image look almost all black, that's good. When a car passes by, you will see the lights from the tail or headlights and hopefully the reflection of the plate and that shutter speed will work well even at high speeds, but remember, getting a shot of a side car is worthless for reading a plate, so you need to be as parallel to the direction of travel as possible. If the image is still too dark to read the plate, what I use for budget installs is a bullet landscape light with a par30 spot light bulb in there, maybe 75W or LED equivalent. On higher-end installs, we use a Raytec RM100 or RM200, runs about $900-1,200 just for the part. As for NVR, because you are looking a specialized cameras for what are trying to achieve, seriously consider decent NVR software like Exacq, Milestone, Avigilon and get a PC to run it on, preferably one rated to be a server. I use Milestone and also use their LPR software, both work well for me and priced competitively. Share this post Link to post Share on other sites