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IR washing out nighttime images

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All,

 

I apologize if there is a thread for this but I did some searches and didn't come up with anything.

 

I have a Q-See. Not sure the model but it can see 80' at night and have 470 TVL. Indoor/outdoor. Actually a decent camera. I wish it was more focused (even in the daytime things appear blurry a bit) but I didnt see any way to open it and try to focus it.

 

Anyway, the reason for my post is that I use the cameras for trying to find out who is breaking into our cars at night. I have this one trained on my Truck in my driveway. The image at night is pretty good (I thought) however the other night my wife took out some garbage and passed in front of the camera on her way back into the house. The camera is mounted about 14' off the ground on my garage and when she was about 10' away on the driveway it got a decent image of her, but then as she got closer she turned into a big, white, blurry ghost. She was wearing a dark shirt and has dark hair.

 

My point is that I am trying to use these to identify someone trying to get into my truck at night, but all I would see is a big, white, blurry ghost which I doubt the police could do much about .

 

There is quite a bit of ambient light out there - lights on the garage, street lights etc. so would a low lux camera instead of an IR camera be better? I tried a few low lux cams from Fry's but they really sucked (cheap ones, less than $150.00).

 

Is this normal for an IR camera to do this at night?

 

Thanks for any opinions or recommendations.

 

Cheers,

 

dave

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cheap IR cameras will just give you blurry images at night. Fact.

 

You have to spend some $ to get clean images with IR.

 

The first thing is an IR cut filter. Second is a aspherical lens that will compensate for the change in focal length with the IR is on.

 

550 TVL is recommended as well. Anything less is just not clear enough.

 

Cameras with this sort of quality start at about $300-400.

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There are several factors you need to take into consideration. First, does the size of the camera matter? There are plenty of low light cameras out there with .002 lux but they require housings for the most part. Second is the budget. Any sub $150 camera with ir will give you blotchy and blurry pictures

because they don't have a filter to go to black and white which is going to give you the sharpest image at night.

 

metafizx is right about the resolution too. You can get 600 lines in black and white or 540 in color. B/W is going to be cheaper.

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cheap IR cameras will just give you blurry images at night. Fact.

 

You have to spend some $ to get clean images with IR.

 

The first thing is an IR cut filter. Second is a aspherical lens that will compensate for the change in focal length with the IR is on.

 

550 TVL is recommended as well. Anything less is just not clear enough.

 

Cameras with this sort of quality start at about $300-400.

 

I can't say I agree with a lot of that.

 

An aspherical lens allows you to open to a wide fstop without it going soft focus it has nothing to do with IR. Perhaps you mean an IR corrected lens? Look into chromatic aberration and remember IR is just like visible light but past red to see how they work.

 

An IR cut filter stops IR so having one on an IR camera kind of defeats the main reason for having an IR camera. Perhaps your thinking about a true day/night camera? That would require an IR cut filter.

 

You have to spend to get clear images with IR. Simply not true. You just need to know what you are doing. The most expensive IR camera has nothing in it that will give you sharper pictures than the cheapest IR (lens excluded). Or if there is I'd love to hear what it is.

 

Here is what I think is happening. The camera is viewing a dark scene, the majority of what it is viewing is not well lit. When your wife walks close to the camera she is being hit by a lot of strong light (forget it's IR just imagine she is standing in front of a headlight). The camera sees a mainly dark scene plus a brightly lit area (your wife). This brightly lit area is not enough to really influence the cameras exposure circuit so it continues applying gain to boost the dark areas and a side effect is it allows your wife to white out.

 

Cameras are dumb and they don't know that your want to see your wife, they have to make a guess and they guess you'd prefer to see the whole scene and allow some areas to be too dark and some areas to white out. We have features like BLC and peak/average to try and get round this but they aren't perfect.

 

To test my theory put some things in the scene that will reflect more IR and make the camera apply less gain. If it works the camera won't clip your wife as much. The down side is the dark areas in the scene will be darker.

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An aspherical lens allows you to open to a wide fstop without it going soft focus it has nothing to do with IR. Perhaps you mean an IR corrected lens? Look into chromatic aberration and remember IR is just like visible light but past red to see how they work.

 

Correct but wont an aspherical lens focus (wrong word) light better on the sensor due to the shape of the curved ground lens?

 

You have to spend to get clear images with IR. Simply not true. You just need to know what you are doing. The most expensive IR camera has nothing in it that will give you sharper pictures than the cheapest IR (lens excluded). Or if there is I'd love to hear what it is.

 

I tend to disagree.....More expensive cameras have better spectral response and therefore are able to see more levels of IR, also more expensive low light cameras may see greater grey levels and therefore more changes of grey.

 

The ability to remove the IR filter obviously enhances the amount of IR light let into the camera, cheper cameras usually do not have this... also the type of ccd and how the pixels are on the CCD actually makes a large difference, some have glass that can spread the light better, some have curved pixels so that light gathers easily around the pixel itself and some can actually change to use multiple pixel blocks at night and single pixel bloks during the day

 

 

Here is what I think is happening. The camera is viewing a dark scene, the majority of what it is viewing is not well lit. When your wife walks close to the camera she is being hit by a lot of strong light (forget it's IR just imagine she is standing in front of a headlight). The camera sees a mainly dark scene plus a brightly lit area (your wife). This brightly lit area is not enough to really influence the cameras exposure circuit so it continues applying gain to boost the dark areas and a side effect is it allows your wife to white out.

 

Agreed, however if the camera could handle the wide dynamic range better or had a more accurate photcell then it would perform better.

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Forgot to add, that if your wife is walking directly towards the camera then the light bounce of IR will be going back to the camera, I assume she walked right in front of it...think of it this way.

 

If you pointed a hose at full strength at me at the bottom of the driveway by the time the water (IR light) reached me I would be wet and not much water (light) would bounce away from my body......but the closer I walk the more water (light) would bounce back towards the camera, therefore the closer I get the closer the water (beam of light) and therefore the strength of the light passing back to your camera is more.

 

This is why inbuilt IR is hardly a good idea, it usually is applied with a fixed lense, therfore it is set to cast its IR to the area that is best in focus...not usually right in front of the camera...the other thing is the light is traveling at the same angle that your camera is viewing so its bouncing straight back...if you used an external device for IR and a more expensive camera with an IR filter you would get a better result...

 

Or to be perfectly honest....why not use a sensor light or slight lawn lights, the best low light cameras around really need very little light indeed.

 

The blurry you may be seeing may not be the light, it might be the CCD holding the light on it to over sample the light a bit like overexposure on a camera, if it keeps the pixels charged for longer then it has more light, the effect is blurry movement, but on still images it looks fine, test fast moving objects to see if your camera has this feature or not.

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I can't say I agree with a lot of that.

 

An aspherical lens allows you to open to a wide fstop without it going soft focus it has nothing to do with IR. Perhaps you mean an IR corrected lens? Look into chromatic aberration and remember IR is just like visible light but past red to see how they work.

 

An IR cut filter stops IR so having one on an IR camera kind of defeats the main reason for having an IR camera. Perhaps your thinking about a true day/night camera? That would require an IR cut filter.

 

You have to spend to get clear images with IR. Simply not true. You just need to know what you are doing. The most expensive IR camera has nothing in it that will give you sharper pictures than the cheapest IR (lens excluded). Or if there is I'd love to hear what it is.

 

Here is what I think is happening. The camera is viewing a dark scene, the majority of what it is viewing is not well lit. When your wife walks close to the camera she is being hit by a lot of strong light (forget it's IR just imagine she is standing in front of a headlight). The camera sees a mainly dark scene plus a brightly lit area (your wife). This brightly lit area is not enough to really influence the cameras exposure circuit so it continues applying gain to boost the dark areas and a side effect is it allows your wife to white out.

 

To test my theory put some things in the scene that will reflect more IR and make the camera apply less gain. If it works the camera won't clip your wife as much. The down side is the dark areas in the scene will be darker.

 

Thanks for your qualifying remarks..

 

I guess I needed to add "IR Corrected" along with "Aspherical" to make the best setup for Day or Night picture quality. If the camera is a sealed unit, then this also adds to the cost of the camera. You dont get this on a cheap camera.

 

And I also meant a Mechanical IR Cut Filter. To provide accurate color during the day without IR distortion, and then brighter Night pictures with the Cut Filter removed. Cameras with a mechnical IR Cut filter are definitely more costly than those without.

 

As for the cost of the camera, you pay more for the better chips (Super HAD, Ex-View, etc) get better quality compensation, higher res TVL. If quality wasn't proportional to cost, then why even bother with more expensive cameras ?

 

As for the white out, the IR might be reflected back into the camera. The AWB/BLC/AE may not respond well with the IR reflection, depending on how good the camera compensates, may cause this image problem.

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Don't ever use a camera with IR actually on it, bottom line. If you want/need IR add an illuminator and install it at least a couple of degrees off. What you are seeing is the IR bouncing straight back into the camera. All the other stuff discusses is fine and dandy and makes a valid point and difference however as long as the incedent IR beam and the cameras FOV are in parallel you will be capturing ghosts.

 

The other point that has been mentioned is cost, this has little to nothing to do with it. You can get sub $100 cameras that do not have this problem however they are all BW and do not have IR on them. So go get a quality BW bullet and IR corrected lens and use that Q-See as an IR illuminator.

 

1/4" CCD and Color scream piss poor low light performance regaurdless of what the marketing on the box says.

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Can anyone explain why having the camera and the light source close together is a bad thing. I'm happy to accept it as true if experience says so but I'd like to understand the reason for it.

 

Here is how my head sees it and it may well be wrong but where I don't know. Everything we see (apart from light sources) is reflected light and all light we see comes straight at us cos light doesn't bend. Now to see something the light has to hit us in the eye. If it whizzed past our ears we wouldn't see it, right?

 

So why would it matter what angle the light was reflected from? All light we see always comes straight from the object to the eye.

 

Headlamps on cars and torches work ok and they are straight out/straight back. Why is this any different?

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It's a percentage deal and it's easy enough to test just get a BW bullet and an IR camera and position it in parallel (which is basically impossible but bare with me) and then again from say a 30* angle.

 

Really you can test this with your eye as well just have put a refective surface infront of you car at night, then position it 30* to the side.

 

 

Heck really this is exactly why when driving in fog if you turn your high beams on you loose visablity. It's because the high beam is not only brighter it's also closer to parallel and hence more gets reflected directly back.

 

Everything you said above is 100% accurate having the beam not in parallel simply reduces the % of light reflected smaller for close objects and 30* seperation is hardly noticable for distant objects.

 

Now since I know you work for someone you obviously (and I mean painfully obvious!) have too much knowledge for an end user. Why don't you go and push for an inexpensive IR illuminator to be produced and sweep the market. They are far far easier to design and really should be dirt cheap, so why are they $2-300? Cause we are too lazy to soulder them up ourselves I guess. No reason you/your organization can't reap those profits.

 

Really take it to the next level and look at a maglite flashlight, really how hard would it be to replace that bulb with an LED array and maintain the focus adjustments? It's a stupid simple concept just has only been applied in mega $ halogen systems.

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Bear with me, I've just come back from the pub so I may read this different in the morning. Are you simply saying viewing something head on it is brighter than if you light it at an angle? Which makes sense but makes me go well yes.

 

However I can see how that causes problems to cameras because their exposure circuits can't cope with low light and bright spots.

 

I don't work in cctv though, I just have a head full of it. Perhaps cynically I doubt many people would make a low cost IR illuminator when they can market expensive ones and make people think IR is something special when in fact it is just a light.

 

Heck, why are high end 1/2" IR exviews so expensive when they are identical to a cheap monochrome except they use a $5 more expensive CCD which is pin for pin identical to the cheap one? Marketing maybe?

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Don't ever use a camera with IR actually on it, bottom line. If you want/need IR add an illuminator and install it at least a couple of degrees off. What you are seeing is the IR bouncing straight back into the camera. All the other stuff discusses is fine and dandy and makes a valid point and difference however as long as the incedent IR beam and the cameras FOV are in parallel you will be capturing ghosts.

 

The other point that has been mentioned is cost, this has little to nothing to do with it. You can get sub $100 cameras that do not have this problem however they are all BW and do not have IR on them. So go get a quality BW bullet and IR corrected lens and use that Q-See as an IR illuminator.

 

1/4" CCD and Color scream piss poor low light performance regaurdless of what the marketing on the box says.

 

I am learning...albeit painfully.

I have used the canned weatherproof cameras with IR builtin, because they are attractive to customers to contain cost, size and ease of installation. But they definitely have their problems.

 

It's very hard to convince customers that the cctv that you buy as a "package" are just junk. Q-SEE and others. But getting them something that is much better quality is expensive. So most customers are looking at the bottom line $, and have a hard time digesting the technical reasons.

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Wow, great discussion people. Thanks!!!

 

So all this being said, we have plenty of light outside on the driveway. We have lights on the garage and a "yellow" street light across the street. If low lux is the way to go, I am all over that, but the "low lux" cameras I have purchased before from Fry's were junk. They said .03 lux but you couldnt see anything beyond about 4'. The light from the garage lights extends all the way to the road. Another irritating thing about these cameras is thier narrow field of view. Seems like I only get about 20' of "view" with them (my Lorax and Q-See IR cameras).

 

What is a good, low lux camera for day/night? Is there such a beast? While we do have most crime commiteed at night, we have enough people wandering our neighborhood during the day to have me want to get images of them. If all else fails, I have a 4 port GV-800 so I could use my 2 cameras during the day and turn them off at night, and switch to 2 low lux cameras. While I cant say "money is no object" I can spend what I need to in order to get night time pictures that are good enough for the Police to ID people breaking into cars.

 

Thanks again for the discussion and the education.

 

Cheers,

 

dave

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Mace has some good low light cameras .002, etc. Those are b/w at night and color during the day. check with Security Monster or one of the other dealers on this site. They'll help you out.

Edited by Guest

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Basically the best perfomance you can get in low light is B/W, but if you want colour in the day then you need a cam that switches between them...if you are doing this, you are going to want a cam that is full body.

 

There are two types of "switch between" or Day Night cams, those that have an IR pass filter and those that dont...IR light is present in things such as Monnlight, so any camera that switches and still blocks the IR light range it could have used will not perform as good as one with a true pass filter.

 

If you go for full body, then you will need to firstly consider the light gathering physical size...IE 1/4 , 1/3rd or 1/2 ...Obviously the larger 1/2 Inch design has more of a surface area for light to gather on the CCD.

 

Next consider the lense...Firstly you need to know if you are using IR lighting and if so you need an IR correct Lense, then you need to again consider how much light can get to your sensor...the first thing to look at is the F Stop, this a measurement...kinda..but not totally....but will do for this example....like measuring the total size of the hole that light can Pass through and again reach your target on the sensor...next decide if you want aspherical or not...aespherical is a curved (again not a great description) back part of the lense, this casts (again simply explained) light better on your target the CCD...Lastly with the lense you need to consider the T Factor, this is the transmittion qulaity and the lack of abhoric abraision on the glass, in laymans terms it means, perfectly machined high qulaity glass with more elements added = greater light transmittion through the lense...so good qulaity lense with nice glass.

 

I doubt you would need to go past this point but next you need to consider your IR beams, seperate is best and the more the light can be seen the better the response..picking something your camera supports is a must.

 

Lastly to avoid blooming and vertical smearing etc, your camera needs to be able to handle low blacks and high whites as well as have an Auto Iris lense...imaginge shining a torch in your eyes and not being able to veen squint.

 

So the best you can go fr would be an aespherical, low F Stop Japanese Glass lense, attached to a 1/2" Low Light performance camera that has an IR Pass filter and is recieving light from an external higher or lower mounted IR Illuminator flood light.

 

To get all this I think you would blow your budget so if it is probably unrealistic..so I give you an expensive...mid and cheap solution below...

 

 

Expensive...either a SDIII from Panasonic, A Bosch LTC0495 atatched to an IR corrected lense that is aespherical and has a low F stop, using UF100 illuminators from Extreeme CCTV

 

Middle Bosch LTC0495 and use your existing cams as Illuminators...similar lense.

 

 

Cheap Any half decent B/W only camera, using your old cams as illuminators

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Basically the best perfomance you can get in low light is B/W, but if you want colour in the day then you need a cam that switches between them...if you are doing this, you are going to want a cam that is full body.

 

There are two types of "switch between" or Day Night cams, those that have an IR pass filter and those that dont...IR light is present in things such as Monnlight, so any camera that switches and still blocks the IR light range it could have used will not perform as good as one with a true pass filter.

 

If you go for full body, then you will need to firstly consider the light gathering physical size...IE 1/4 , 1/3rd or 1/2 ...Obviously the larger 1/2 Inch design has more of a surface area for light to gather on the CCD.

 

Next consider the lense...Firstly you need to know if you are using IR lighting and if so you need an IR correct Lense, then you need to again consider how much light can get to your sensor...the first thing to look at is the F Stop, this a measurement...kinda..but not totally....but will do for this example....like measuring the total size of the hole that light can Pass through and again reach your target on the sensor...next decide if you want aspherical or not...aespherical is a curved (again not a great description) back part of the lense, this casts (again simply explained) light better on your target the CCD...Lastly with the lense you need to consider the T Factor, this is the transmittion qulaity and the lack of abhoric abraision on the glass, in laymans terms it means, perfectly machined high qulaity glass with more elements added = greater light transmittion through the lense...so good qulaity lense with nice glass.

 

I doubt you would need to go past this point but next you need to consider your IR beams, seperate is best and the more the light can be seen the better the response..picking something your camera supports is a must.

 

Lastly to avoid blooming and vertical smearing etc, your camera needs to be able to handle low blacks and high whites as well as have an Auto Iris lense...imaginge shining a torch in your eyes and not being able to veen squint.

 

So the best you can go fr would be an aespherical, low F Stop Japanese Glass lense, attached to a 1/2" Low Light performance camera that has an IR Pass filter and is recieving light from an external higher or lower mounted IR Illuminator flood light.

 

To get all this I think you would blow your budget so if it is probably unrealistic..so I give you an expensive...mid and cheap solution below...

 

 

Expensive...either a SDIII from Panasonic, A Bosch LTC0495 atatched to an IR corrected lense that is aespherical and has a low F stop, using UF100 illuminators from Extreeme CCTV

 

Middle Bosch LTC0495 and use your existing cams as Illuminators...similar lense.

 

 

Cheap Any half decent B/W only camera, using your old cams as illuminators

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Basically the best perfomance you can get in low light is B/W, but if you want colour in the day then you need a cam that switches between them...if you are doing this, you are going to want a cam that is full body.

 

There are two types of "switch between" or Day Night cams, those that have an IR pass filter and those that dont...IR light is present in things such as Monnlight, so any camera that switches and still blocks the IR light range it could have used will not perform as good as one with a true pass filter.

 

If you go for full body, then you will need to firstly consider the light gathering physical size...IE 1/4 , 1/3rd or 1/2 ...Obviously the larger 1/2 Inch design has more of a surface area for light to gather on the CCD.

 

Next consider the lense...Firstly you need to know if you are using IR lighting and if so you need an IR correct Lense, then you need to again consider how much light can get to your sensor...the first thing to look at is the F Stop, this a measurement...kinda..but not totally....but will do for this example....like measuring the total size of the hole that light can Pass through and again reach your target on the sensor...next decide if you want aspherical or not...aespherical is a curved (again not a great description) back part of the lense, this casts (again simply explained) light better on your target the CCD...Lastly with the lense you need to consider the T Factor, this is the transmittion qulaity and the lack of abhoric abraision on the glass, in laymans terms it means, perfectly machined high qulaity glass with more elements added = greater light transmittion through the lense...so good qulaity lense with nice glass.

 

I doubt you would need to go past this point but next you need to consider your IR beams, seperate is best and the more the light can be seen the better the response..picking something your camera supports is a must.

 

Lastly to avoid blooming and vertical smearing etc, your camera needs to be able to handle low blacks and high whites as well as have an Auto Iris lense...imaginge shining a torch in your eyes and not being able to veen squint.

 

So the best you can go fr would be an aespherical, low F Stop Japanese Glass lense, attached to a 1/2" Low Light performance camera that has an IR Pass filter and is recieving light from an external higher or lower mounted IR Illuminator flood light.

 

To get all this I think you would blow your budget so if it is probably unrealistic..so I give you an expensive...mid and cheap solution below...

 

 

Expensive...either a SDIII from Panasonic, A Bosch LTC0495 atatched to an IR corrected lense that is aespherical and has a low F stop, using UF100 illuminators from Extreeme CCTV

 

Middle Bosch LTC0495 and use your existing cams as Illuminators...similar lense.

 

 

Cheap Any half decent B/W only camera, using your old cams as illuminators

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There are two types of "switch between" or Day Night cams, those that have an IR pass filter and those that dont...IR light is present in things such as Monnlight, so any camera that switches and still blocks the IR light range it could have used will not perform as good as one with a true pass filter.

 

 

Are u talking about "pass" or "cut filter ?

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Don't ever use a camera with IR actually on it, bottom line. If you want/need IR add an illuminator and install it at least a couple of degrees off. What you are seeing is the IR bouncing straight back into the camera. All the other stuff discusses is fine and dandy and makes a valid point and difference however as long as the incedent IR beam and the cameras FOV are in parallel you will be capturing ghosts.

 

The other point that has been mentioned is cost, this has little to nothing to do with it. You can get sub $100 cameras that do not have this problem however they are all BW and do not have IR on them. So go get a quality BW bullet and IR corrected lens and use that Q-See as an IR illuminator.

 

1/4" CCD and Color scream piss poor low light performance regaurdless of what the marketing on the box says.

 

I am learning...albeit painfully.

I have used the canned weatherproof cameras with IR builtin, because they are attractive to customers to contain cost, size and ease of installation. But they definitely have their problems.

 

It's very hard to convince customers that the cctv that you buy as a "package" are just junk. Q-SEE and others. But getting them something that is much better quality is expensive. So most customers are looking at the bottom line $, and have a hard time digesting the technical reasons.

 

another comment about the canned weatherproof cameras with builtin IR.

 

I recently realized that the cause of severe haze at night was due to dried residue from rain splashes, causing bounceback of IR into the camera.

 

use of separate IR illuminator and camera w/o IR would not have this problem. Or a IR camera that is designed to reduce IR reflections from the glass plate.

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Don't forget insects and spiders, both seem to like IR and both will botch your picture and nothing much you can do about it.

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I have noticed that about the insects. About twice a week I have to clean the lenses.

 

I have done a search for "Security Monster" on the message bases to try and contact that person about getting new cams but there were no hits on this. While I dont mind using one of the click thru ads, I would prefer to use someone who has been used and been recommended vs. just someone who is advertising on the site.

 

I thought I knew what I needed but cctv_down_under got me confused again! . I thought I wanted to get away from IR and just into a very good low lux camera. Guess what I need to do is choose a vendor, call them, discuss what this discussion has been about and have them recommend a system for me.

 

Thanks again everyone for your help. FYI - the local news here in Vegas picked up on my security video of the guys trying to break into my car and ran the story on the 11:00 news last night including the video. Hopefully there wont be any repercussions from vengeful car break-in people.

 

Cheers,

 

dave

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