bpzle 0 Posted August 13, 2009 I'm looking to cover a parking lot with no curbs for a main entrance from the street. Basically the entire width of the parking lot can be entered from any point from the street that runs parallel with it. The size of the lot is 60 feet x 110. It has very little to no light at night. I'm interested in catching plates of vehicles both parked and entering/exiting the lot. I was thinking a minimum of 2 seperate, 3-5 megapixel cams mounted for wide angle shots. So far I have been impressed with demos from both Arecont and Mobotix. I will be using a hybrid NVR on site so while the Mobotix built in records are nice, it would only serve as backup purposes. Q1: What would you suggest for megapixel IP cameras? Q2: What lens type? Q3: What IR floods? Q4: What housings? Can a typical blower/heater housing for an analog camera suffice? Share this post Link to post Share on other sites
megapixel man 0 Posted August 14, 2009 I'm looking to cover a parking lot with no curbs for a main entrance from the street. Basically the entire width of the parking lot can be entered from any point from the street that runs parallel with it. The size of the lot is 60 feet x 110. It has very little to no light at night. I'm interested in catching plates of vehicles both parked and entering/exiting the lot. I was thinking a minimum of 2 seperate, 3-5 megapixel cams mounted for wide angle shots. So far I have been impressed with demos from both Arecont and Mobotix. I will be using a hybrid NVR on site so while the Mobotix built in records are nice, it would only serve as backup purposes. Q1: What would you suggest for megapixel IP cameras? Q2: What lens type? Q3: What IR floods? Q4: What housings? Can a typical blower/heater housing for an analog camera suffice? You will need to have the whole parking lot covered with effective "pixels on target" to read license plates to meet your spec detailed above. Doing some quick calculations and a very rough mud map (converting feet to metres etc...), you will need 6x 5MP Cameras to do the job properly and have 100% coverage. Lenses will vary depending on the cameras selected (sensor formats) but will typically be in the range of 2.8-12mm, they will ned to be of the IR corrected type. Have a look at the Raylux IR illuminators, these will also have to give the parking lot 100% coverage. In regard to housings, if you use a "full body" / "box" style camera then the typical analog camera housings with heater blower may suit. try to get some camera / lens resolution estimation tools from the camera manufactures you work with to do the sums for yourself. Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 For license plate recognition you need 45PPF with Arecont cameras. So with a required pixel density of 45 a 5 megapixel Arecont camera will give you a horizontal field of view of 58ft. So I agree with Megapixel Man (6) AV5105DN's should do the trick. It doesn't matter what lens you have on the camera your FOV of 58ft will not change. What does change with different lens is your distance to pixel density. Pick your camera first, lens last. Share this post Link to post Share on other sites
bpzle 0 Posted August 14, 2009 For license plate recognition you need 45PPF with Arecont cameras. What's PPF? Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 For license plate recognition you need 45PPF with Arecont cameras. What's PPF? Pixels Per Foot Share this post Link to post Share on other sites
hardwired 0 Posted August 17, 2009 When setting up license plate recognition, you also want to go with the highest shutter speed possible to reduce motion blur. If you have your cameras near the illuminators, and have reflective plates, this can result in a great picture of a plate, but floating through black space. You may want to add an lower resolution, higher sensitivity cam as a wide overview for all the activity area, and cross tighter shots from the megapixels in a way to catch the plates as close to head on as possible. White lighting (if you can) would add overall deterrence value, and let you determine color of cars, which you cannot under IR. Also, some plates will not resolve well under IR (AK357 up in Canada has white plates with red numbers, almost no contrast) Share this post Link to post Share on other sites