camera selection

[ringtone]

Maybe someone here could help me find the correct camera for my application. This camera will point down a driveway, so I would like a day/night camera that could pick up a license plate at about 75 feet. Any suggestions would be greatly appreciated.

- John

[CCTV Blog Admin]

It really is going to depend on lighting, lens size and the cameras capability. If you have lighting already or the lighting is good. You can use a bullet camera with a vari-focal lens to achieve a good picture. Look for the lux rating on the camera. It should at least .001 or so. Keep in mind your picture will narrow when you zoom in. You can use a full size camera with a housing but it sounds like you need something simple. If lighting is an issue I would suggest a bullet with long range IR, vari-focal lens and mechanical IR filter. Just look this up on google I am sure you will find many cameras with these specs or I'm sure someone in this community will have something for ya.

[ringtone]

I actually bought the Nuvico CB-SD21N-L bullet camera. It has the specs mentioned, but the picture quality is still pretty low. There is no way I could read a sign or license plate. Could it be that a camera with a larger ccd than 1/3" might do the trick?

[CCTV Blog Admin]

Actually that camera is .1 lux not .001 but thats ok. The problem sometimes is IR range with the lens size. Are you getting a blurry picture or would you say you have a lot of noise on the picture.

[ringtone]

That is a good question. I am not sure how to determine the difference between a blurry picture and a camera that needs a better lens or one that needs more picture lines. The bottom line is that the picture does looks blurry to me, even though I have the camera focused as much as possible. The other problem I had early this morning is blooming from the reflection of the sun on the driveway.

[CCTV Blog Admin]

Well the blooming is an issue. WDR is the choice for most with this issue. WDR products are hit and miss. I have yet to really find a great solution for WDR. Digital slow shutter should help with picture quality and is an option. Especially if there is no movement and you are looking at a license plate. A strong IR camera with a bigger lens should be fine though without breaking the bank. I would also adjust your camera at night or use a welders block to adjust it properly so you don't get focus shift. That can be your problem also.

[ringtone]

Any specific cameras you suggest?

[Brandon Joubert]

For that level of identification at 75 feet you'll need nothing less than a 50mm or 60mm lens.perhaps even larger. We have IR day Night cameras with that focal length, as well as motorized lens versions. The motorized zoom lens work with a controller box and we have installed some on PTZ motors. With a standard IR camera though you will not be able to pick up the plates at night as the headlights of a vehicle will blind the camera.

We have tested some LPR cameras which override the headlights at night and have excellent effect, but you'll still need a massive focal length for identification at 75 feet.

[ringtone]

Brandon,

How much should I expect to pay for a camera with the specifications of a day/night camera with a 50mm or 60mm lens?

Do you know of specific models that you like?

- John

[Brandon Joubert]

Standalone camera, perhaps $190, controller around $30-40, and if you want to put it on a PTZ motor around $50-60. But i don't know what the prices are like in your local area.

[Brandon Joubert]

You might also try an IR Array Camera -- but that would become pretty expensive.

[Brandon Joubert]

Given the blooming issue you mentioned in the mornings, this is quite a normal occurrence and one either lives with it or gets a WDR camera, once again this option may become rather pricy with that lens size.

[Brandon Joubert]

Regardless -- at that distance, vehicle headlights, and morning sunlight create a formidable challenge. This begs asking ---Is license plate recognition really essential to the application?