13 replies to this topic

[247]

Help Needed please

I have a job to install the customer wants to be able to get the number plates of all the cars entering his site in all external lighting conditions , now in tha past i have used the Derwent ANPR cameras whiched worked well, however as always this guy is on a budget.

Any ideas what would work just as well (if anything) for maybe half the cost of a usual ANPR £1100 the external lighting is already budgeted for so its just the camera and lens im concerned about

Any ideas would be much appreciated

Paul

[247]

PaulR, on Feb 17 2005, 09:01 AM, said:

Do you require number plate recognition software, or just to be able to read the number plate as it passes the camera?

Hi

I just need to be able to read the number plate, maybe in the future add the software but for now just read

Thank you

[247]

PaulR, on Feb 17 2005, 05:37 PM, said:

Something like this

the camera

with a good lens like this

a lens

should do the trick, in an exterior housing - assuming it is attached to a good recording/control medium and monitor. Have you considered the DVR or VCR equipment yet?

Thanks for that however this camera will not be able to deal with all lighting conditions,

Paul

[secboy]

247, on Feb 18 2005, 12:37 PM, said:

Thanks for that however this camera will not be able to deal with all lighting conditions,

Paul

I'M interested! the spec looks ok for day night and IR why don't you think it will do the job on a budget?Paul(essex)

[Rich]

Is this the room where if your namesw is not Paul your not coming in?

Paul.

[247]

Hi

I have tried before and where it is so dark where the headlights shine on the camera the glare is so bad i could not read the plates, the best answer so far is to use a Samsung SHC-721 with WDR which helps a lot with the lighting conditions and a good lens like the one in the previous post

http://www.247cctvse...ads/SHC-721.pdf ..

Thanks to all that replied

Paul

[secboy]

247, on Feb 18 2005, 05:41 PM, said:

Hi

I have tried before and where it is so dark where the headlights shine on the camera the glare is so bad i could not read the plates, the best answer so far is to use a Samsung SHC-721 with WDR which helps a lot with the lighting conditions and a good lens like the one in the previous post

http://www.247cctvse...ads/SHC-721.pdf ..

Thanks to all that replied

Paul

I remember a camera off the shelf which which blanked out car headlights and all the glare can any one think who made it or what the feature was called????Paul.

[Doktor Jon]

Paul,

The technique you're describing is known as 'luma - key', where an area of highlight is overlaid with a 'matt' to suppress it's effect on the auto iris lens function. I vaguely remember this being available on one or two high end cameras (possibly Philips or Grundig but not sure), but it was originally available as an add on box; two which immediately spring to mind are 'eclipser' and 'halo' both of which are now long since defunct.

The trick with number plate recognition is to reduce the lighting ratio in vision, and this is usually done by increasing the level of illumination on the vehicle itself (e.g. mostly using Infra Red with a B/W camera), so that the camera is not being asked to handle such a wide lighting range. You can also significantly reduce the effect of vehicle headlights by choosing an ideal (off centre) position for the camera.

Use of shuttering, either one or two stops with an electronic shutter, or alternatively a slightly stopped down manual iris lens and Electronic Iris function, will significantly sharpen up the number plate image, by reducing the blurring caused by the vehicles movement.

Depending on where the number plate recognition is being used, it is generally easier to pick up the rear plate (usually less dirt, less intense vehicle lighting and the plate should be lit), particularly in applications like well lit petrol stations.

[Doktor Jon]

I've not come across the 'eclipse' camera; any idea who the manufacturer is...?

The 'eclipser' unit I mentioned used to be manufactured (?) / distributed by a company called Evershed Power Optics, but I've no idea what happened to them.

[secboy]

Hi doc jon i see your having a look!!!Paul Ive recalled that the last time i saw this camera was for very bad light levels in a car park with no chance of IR,s due to the budget so i went for a high res monochrome which i think may have been a sony or sanyo as colour was less inportant than quality it worked very well and automatically blacked out headlights it would have come thru Norbains so perhapes a chat with their tech support will help!!Paul.

Edited by secboy, 23 February 2005 - 10:13 AM.