Dahua - Spec new system - how to disarm all cameras active deterrence and are the lower MP cameras really better at night?

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Hi All,

I'm speccing out a new system and have some less technical users. I realise I can run the active deterrence on a schedule but what I really need is the ability to arm/disarm the entire perimeter (6 cameras) with one click.

There was an earlier thread which suggested that turning them off was the most effective way - I am hoping we have moved onto something more sophisticated.

e.g. Can the app disarm a set of cameras? Or can you interface a physical switch / alarm control panel to achieve the same outcome?

It also has been suggested that the lower MP cameras are better at light - more light per pixel, makes sense. Any real world experience? (all things being equal I would choose 8 MP but not if the low light performance is poor)

Cheers
 

wittaj

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Yes, avoid the 8MP active deterrence. I run Blue Iris, so I created a batch file that allows me to turn them off/on with one "button" in the app. I am not sure if the NVR has that capability.

Chase sensor size, not MP.

Keep in mind that the active deterrence cameras are good as overview cameras, but will not IDENTIFY someone unless they are 10ish feet or so away, but that goes for any 2.8mm fixed lens camera. Do not think this camera is the be all, see all, do all.

The distance to be covered from the camera to the object location is the most important factor and more important than MP.

You need to identify the areas you want to cover and pick a camera designed to cover that distance. In some instances, it may be a 2MP or 4MP that is the right camera. DO NOT CHASE MP!!!

It is why we recommend to purchase one good varifocal and test it at all the proposed locations day and night to figure out the correct focal lengths and cams.

A few other tips....It is simple LOL do not chase MP - do not buy a 4MP camera that is anything smaller than a 1/1.8" sensor. Do not buy a 2MP camera that is anything smaller than a 1/2.8" sensor. Do not buy a 4K (8MP) camera on anything smaller than a 1/1.2" sensor. Unfortunately, most 4k (8MP) cams are on the same sensor as a 2MP and thus the 2MP will kick its butt all night long as the 4k will need 4 times the light than the 2MP... 4k will do very poor at night unless you have stadium quality lighting (well a lot of lighting LOL).


That 3849 active deterrence camera is an 8MP on a 1/2.8" sensor, so it is on a horrible MP/sensor ratio. You cannot have enough light at night for it to perform well.

Even worse, this 8MP is on the same sensor and CPU as a 2MP non TIOC camera and there are many threads here showing how under-performing that 3849 is. They had to limit bitrate and other parameters on the 3849 to try to make it functional, and it just doesn't cut it.

In my opinion the 3849 should not be sold with that current MP/sensor and CPU combination, but alas everybody wants 4k and chases MP over sensor and this camera is the epitome of that thinking.

Further, the red/blue flashing lights are more gimmicky and are certainly not a deterrent. With any ambient light you won't see the red/blue flashing unless you are looking right at the camera.

If you want active deterrence, your best bet is to go with the 2MP IPC-T5241H-AS-PV that will blink the white light. This is on the ideal MP/sensor ratio and will perform comparably to any similar 2MP fixed lens camera by Dahua. I have two of them. I have some of the other active deterrence cams as well, and would opt for the 2MP in every instance except for indoor, one could go with the IPC-HDW3449HP-AS-PV that has the red/blue lights that will bounce off the walls and be much more impressive than outside.

Lot's of threads here where people showed how bad the 8MP camera is in performing:





 
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