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harley1

Need better cameras?

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I am getting way to many motion alerts from my current system. I have Aposonic cameras... the $55 ones.

 

My dvr manufacturer said that the cameras are producing to grainy of an image and I need to upgrade. Okay, I'll buy that. I am unsure what spec I need to look for when purchasing new cameras. The current cameras are having trouble adjusting to changes in ambient lighting during the day. Sky goes cloudy? That could mean 8-10 alerts.

 

So, camera recommendations in the $100 each range? And what specs need I pay attention to for the aforementioned issues?

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It's really hard to say what the REAL cause of the problem is without seeing a video clip... and the same goes for the "DVR manufacturer" (of course he's going to blame the cameras before saying there's anything wrong with the DVR or its settings). If ambient light changes are triggering motion recording, it's unlikely a different camera will solve the problem.

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I am getting way to many motion alerts from my current system. I have Aposonic cameras... the $55 ones.

 

My dvr manufacturer said that the cameras are producing to grainy of an image and I need to upgrade. Okay, I'll buy that. I am unsure what spec I need to look for when purchasing new cameras. The current cameras are having trouble adjusting to changes in ambient lighting during the day. Sky goes cloudy? That could mean 8-10 alerts.

 

So, camera recommendations in the $100 each range? And what specs need I pay attention to for the aforementioned issues?

 

Look at the CCD Resolution, as well as something that can do Day/Night - so a camera with IR LEDS !

The other reply about a better DVR is true as well, also make sure to mount them in a good location (IE not looking up at the sky)

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If ambient light changes are triggering motion recording, it's unlikely a different camera will solve the problem

That. No way around that I don't believe. Try lowering the sensitivity a bit.

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The cameras I'm using are day/night cameras with led IR. They are also not looking at the sky.... just the driveway and entryway to my home. They are mounted under the eaves around the perimeter of my home. I currently have the sensitivity set a low as the dvr will allow.

 

I am going to try a new cameras in place of my existing cameras. I am currently in between systems. I had an IP system but I was replacing 3-4 cameras every summer. Arizona summers eat cameras and I was tired of shelling out $300 x 4 every summer. I decided to go with an analog cctv system so I could replace the cameras without sacrificing my wallet.

 

I want to know what criteria I should be looking for when purchasing cameras in the low $100 range if in fact the grainy image is contributing to my dvr's excessive motion alerts. According to the dvr manufacturer, the minimum setting should require a school bus in my front yard to trigger an alert.

 

My questions are:

1) What criteria do you guys think would most likely fix my problem (more lines, auto iris, anti flickering, etc)?

2) What camera (turret style preferred) might you recommend in the low $100 range since I may have replace them every summer?

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Camera noise at low light can be a problem for motion detectors. To reduce noise you should increase light, use more sensitive cameras or cameras with noise reduction function, but they are expensive. Try also cameras with low maximum AGC gain.

In low light such cameras produces dark images but without noise. Some cameras has adjustable AGC so you should set LOW AGC. After changing camera you should readjust motion detector sensitivity.

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I would make certain the MD is off on the cameras and use only the detection on each channel in the drv and set each channel accordingly to the needs of the FOV. It's likely that the MD in the dvr is much more forgiving of low light noise at night, which will allow you to bring up the sensitivity accordingly on each channel. This has been my experience, at least.

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You're losing 3-4 cameras every year? To what? Heat?

 

For that kind of money, I'd start installing fans on them or something... that's nuts.

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Yep, heat. Arizona summers can reach close to 120F for multiple days in a row. Although most cameras are rated for 122F, or close to it, that rating doesn't quantify for how long. Usually what happens is the internal capacitor over heats and bursts and that is the end of the camera. I have considered different remedies (have an m.s. in engineering... so many ideas) but ultimately decided on abandoning my old gear in favor of a cctv setup.

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Yep, heat. Arizona summers can reach close to 120F for multiple days in a row. Although most cameras are rated for 122F, or close to it, that rating doesn't quantify for how long. Usually what happens is the internal capacitor over heats and bursts and that is the end of the camera. I have considered different remedies (have an m.s. in engineering... so many ideas) but ultimately decided on abandoning my old gear in favor of a cctv setup.

 

Or you could go with some higher-quality IP cams. Mobotix cameras are rated up to 140F

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Looks cheap imho. I don't think it is the right solution to look for cheap cameras that you can replace every year. I would look into high quality cameras that will just work in the heat or try to figure out a way to cool the cameras.

 

Internal IR might also create additional heat and thereby kill the cameras even faster.

 

I really cannot name a camera that will work at this heat, but this is just because I never look at the maximum operating temperature. I always have to look at the minimum operating temperature.

 

Why don't you ask a local Security company? They should know what to use...

 

Edit: You might want to look for a dome in a metal housing - to get the heat out faster...

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IR will create more heat as mentioned (although only at night).

Best thing would be to look for a low current 24VAC camera that sees in very low light.

Then add the IR separately if needed.

But the other important thing is to make sure the housing is white.

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Edit: You might want to look for a dome in a metal housing - to get the heat out faster...

Your analogy is incorrect. The heat source is the ambient air and the sun, not the camera. This is convection and radiation heat transfer that is entering the camera housing, not exiting. Plastic is actually a better insulator to help prevent heat transfer.

 

 

As Rory mentioned, the IR is only on at night when outside temperatures are lower. I highly doubt that the LEDs generate a significant amount of heat to do any damage. However, this is quantifiable. Simply determine the wattage difference of the camera when the IR is on and when it is off. The difference of wattage is the amount the IRs use. Watts is a measurement of heat.

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Edit: You might want to look for a dome in a metal housing - to get the heat out faster...

Your analogy is incorrect. The heat source is the ambient air and the sun, not the camera. This is convection and radiation heat transfer that is entering the camera housing, not exiting. Plastic is actually a better insulator to help prevent heat transfer.

 

I don't agree. The camera electronics produce the heat. The temperature inside the camera box is always higher than the environment temperature. The higher environment temperature is the higher temperature inside the box. Then the temperature inside the box exceeds max allowed one, the camera will be overheated.

 

The difference between box temperature and environment temperature depends of camera power consumption and heat resistance, which depends of box material, form, wind speed. Additional heat is produced by the sun. The darker camera color is the more sun heat it collects.

 

To prevent overheat it is better to place cameras in shadow, use anti-sun shields, use heatsinks, white color cameras in metal boxes.

Also you should decrease power consumption, don't use build-in IR, use minimum allowed supply voltage..

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I could have explained that a bit better... the heat source the kills my cameras is the outside air temperature. However, I encourage you to do the calculations to determine if the inside camera temperature is higher than the outside air. Knowing the the camera housing's material coefficients are less than 1, you could calculate the heat transfer across the body of the camera and summing the heat loss from the inefficiency of the camera's electronics you could arrive at the total temperature inside the camera. Knowing how little wattage cameras use I would be inclined to neglect the energy losses due to inefficiency. Most electronics are near 99% efficient.

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I could have explained that a bit better... the heat source the kills my cameras is the outside air temperature. However, I encourage you to do the calculations to determine if the inside camera temperature is higher than the outside air. Knowing the the camera housing's material coefficients are less than 1, you could calculate the heat transfer across the body of the camera and summing the heat loss from the inefficiency of the camera's electronics you could arrive at the total temperature inside the camera. Knowing how little wattage cameras use I would be inclined to neglect the energy losses due to inefficiency. Most electronics are near 99% efficient.

 

May be you don't believe me , but our problem is opposite - frost. When a camera is working, it produces enough heat for working even in strong frost. But the same camera can't start after non working period in frost. Actually all electric power consumed by camera (0.15A*12V=1.8Watt) is transformed to heat except of electric power of output videosignal in cable (no more than 0.01Watt). There is no way for output energy from camera except the heat and the videosignal.

 

Use a digital multimeter with thermopair sensor to measure the temperature inside camera box after working in several hours. Then compare it with environment temperature. It can be interesting.

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Edit: You might want to look for a dome in a metal housing - to get the heat out faster...

Your analogy is incorrect. The heat source is the ambient air and the sun, not the camera. This is convection and radiation heat transfer that is entering the camera housing, not exiting. Plastic is actually a better insulator to help prevent heat transfer.

 

 

As Rory mentioned, the IR is only on at night when outside temperatures are lower. I highly doubt that the LEDs generate a significant amount of heat to do any damage. However, this is quantifiable. Simply determine the wattage difference of the camera when the IR is on and when it is off. The difference of wattage is the amount the IRs use. Watts is a measurement of heat.

 

Are you suggesting that it is cooler inside the camera housing? There is working electronic in there and I would not know why it should be cooler than outside...

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I am saying it 'could be' cooler inside than out. Yes. I am saying that the outside air condition's inability to transfer 100% of its heat energy to the inside of the camera may cause the inside to be cooler. A simple, and very basic example, is a ham cooking inside your oven. If you set the oven temperature to 350F and let the ham cook a few hours you will find that the temperature inside the ham would be about 200F. The reason is because the ham doesn't absorb all the oven's heat because the ham's material isn't perfectly efficient. Again, a simple example.

 

If you do the math to determine the inside camera temperature as a result of the outside temperate may find that the camera's body doesn't transfer all of the external heat energy to the inside. My camera's are 6 watts. Watts is Joules/second. If you calculate the amount of heat generation from the electronics, which I believe to be small, and sum it to the secondary heat (heat entering the camera from outside) and allow steady state conditions to exist you may find that inside temperature never reaches the outside temperature.

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I get your point and I honestly can't compete with your math, but in my experiance most cameras produce heat. Many camera housings feel warm when touched and therefore I cannot imagine that it would be cooler inside the camera.

 

I would even go so far and say that it would probably extend the live of the camera if it had a metal housing and a tiny fan that blows onto the PCB to make sure the heat is quickly carried elsewhere.

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Point taken. I'm not trying to flame anyone or try to push the math on anyone. I came to this forum for help because you guys know more than me.

 

I began this post looking for camera specifications that may quiet my dvr down because its spamming me all day with messages containing pictures of nothing. I am unsure if I should be looking for a camera with 650+ lines or one with high noise reduction. I am guessing noise reduction is the best way.

 

I have considered adding fans to try to cool the camera electronics and capacitors, but I believe that the fan motors would generate interference with the camera... think running the vacuum or a blender while watching tv. In my house that would mean a very fuzzy tv picture.

 

I have spent so much money replacing cameras over the years I cannot bring myself to buy another $300 camera only to have it die this summer.

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Point taken. I'm not trying to flame anyone or try to push the math on anyone. I came to this forum for help because you guys know more than me.

 

I began this post looking for camera specifications that may quiet my dvr down because its spamming me all day with messages containing pictures of nothing. I am unsure if I should be looking for a camera with 650+ lines or one with high noise reduction. I am guessing noise reduction is the best way.

 

I have considered adding fans to try to cool the camera electronics and capacitors, but I believe that the fan motors would generate interference with the camera... think running the vacuum or a blender while watching tv. In my house that would mean a very fuzzy tv picture.

 

I have spent so much money replacing cameras over the years I cannot bring myself to buy another $300 camera only to have it die this summer.

 

Many PTZ cameras have small fans inside of them. This should not create any interference. It would be good to see your recording or at least a picture of a camera when there is noise. This could help identifying the problem.

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I haven't considered PTZ cameras. I didn't know they had fans in them. They must have a ground loop isolator to prevent low level emf interference. Get what you pay for I guess.

 

I have attached a few pictures taken just a short time ago.

CH01_12_01_23_10_48_33.jpg.1ca2ccf91707f840bc5301ebfa131b72.jpg

CH02_12_01_23_11_01_42.jpg.be47dc51313a15ddaf842be17fb48d04.jpg

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