harley1

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?

Me either! I do have the sensitivity set to the dvr's minimum. I could try adjusting the color settings of each camera but I am not very hopeful about that. As an experiment the other day I set 1 camera's motion zone to about 1 square foot area on a portion of the driveway. I still got motion alerts. Weird.

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.

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.

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.

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.

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.

I think I found a camera that fits my needs in both performance and budget. Any thoughts? http://www.digimerge.com/product/dcv24dl-varifocal-600tvl-ir-dome/

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.

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?