aurmol

Because the external router uses 192.168.1.1. Should I set it to 10.1.1.1? A separate question. At night in one of the dahua cameras. I need to set it to night mode so IR will turn on.. because it is still in colors even though the sides are dark. Is it possible to set the NVR so that at certain time, the night mode IR is enabled? You can't connect your camera like that. You will have to connect it directly to the nvr. I'm not sure about the night vision being turned on automatically. Let's say the dahua NVR has 8 channel but only 4 built in poe ports. You'll need a separate external router. My question is whether the router can be 192.168.1.1 and camera connected to it be 192.168.1.* and the internal poe switch 10.1.1.1.. so can these separate ip be mixed.. thanks.

Because the external router uses 192.168.1.1. Should I set it to 10.1.1.1? A separate question. At night in one of the dahua cameras. I need to set it to night mode so IR will turn on.. because it is still in colors even though the sides are dark. Is it possible to set the NVR so that at certain time, the night mode IR is enabled?

The ip configured is 192.168.1.4 and default gateway is 192.168.1.1 the internal switch setting is 10.1.1.1 so from experience you can mix cameras of different ip addresses? In the p2p recorder that is hard to connect.. what is the numbers of cameras connected? I have only use up to 4 channels but never have experienced with using more than 4.

but the other brand camera (jovision) won't go online when connected to a router with address 192.168.1.1. Should I set the router to 10.1.1.1 (just like the other dahua connected to the internal ip) too? or should 192.168.1.1 theoretically work? Well. I have to use 2 dahua NVR- 4 channel each because a single 8 channel NVR may really be saturated. Connection takes long in either but at least it still loads up. Why how many times longer did your clients experience in connecting p2p?

Hi, I have this Dahua recorder with built in POE with address 10.1.1.1. The 2 cams also made by dahua connected fine. But an external other brand camera connected to external router with 192.168.1.1 can't go online. Should the external router ip be set to 10.1.1.1 also? A separate question. Supposed there are 2 internet broadband access points connected to your network (I only have one but just asking in case there are two) and there is one dahua recorder with P2P access. When you access it remotely.. which of the 2 broadband access points would it use? is it random or how does it choose? Thank you.

The most logical is they default the exposure to 1/30 (even if it's on auto) at all low light targets to avoid motion blur. So instead of the 2Mp setting of the 3Mp needing more exposure (they just set it to 1/30). This explains all the noises of the 2Mp. By the way. The same S/N noise is present in the HD-CVI camera I tried before too. So at low light, it uses 1/30 instead of say 1/10.. to avoid motion blur. Maybe the S/N in the sensor not so efficient that is why not enough signal and requiring slower exposure. That said. I'd move over all this cctv now and go back to this years later when dahua produce a 12mp with incredible low light performance (if this wil exist at all in small sensors... maybe someday when adaptive optics with quantum entangled detection methods (like how the robin birds use quantum entanglement in their retinas to see magnetic fields) are used to make those tiny sensors perform like DSLR).

to continue above, the following is what occurred when the dahua 5mp and its 1080p setting (in red rectangle) is overlap transparently (just learnt this trick from Maxicon.. thanks and sorry for the off topic).

I tried the trick in the 4300s. The 2MP and 3MP images are directly taken from the sensor. But I've been thinking of something since days ago when comparing the noise. And you mentioned the issue when you said "note the exposures are different due to the different FOV". In the camera. Do they use separate light exposure sensor for the whole image or pixel by pixel? Because if it's pixel by pixel, the light should be the same no matter what part of the sensor you take the images (whether 2mp or 3mp). Yet in the noises comparisons I did. I noticed the reason the 2mp version of the 3mp 4300s is noisier is because they use the same exposure for both even its in auto... let's say 1/30. Because the noise present are light exposure noises, not compression noise (I studied the difference between S/N vs compression artifacts). So if I adjust the exposure of the 2mp version to make it say 1/25, the noises are better or almost equal to the 3mp. But at that time I figured exposure shouldn't vary with fov because the same pixel in the sensor pick up the same light (remembering the images on the lens sides go to the sensors at the sides.. so you just get the images of the sensor at center, the light should be the same). Btw.. trying the transparent trick (which I just learnt to do after years of using image editing), I found out the 1080p version of the dahua 5mp are directly taken from sensor, that is why the field of view is just one half, while that of 720p are compressed smaller from the original image (with D1 they took the center image and make it smaller). The 3mp version of the 5mp are taken directly from sensor with about 10% increase so the field of view is still half of the 5mp. I see more details at night in the 3mp 4300s than the 5mp that was why I returned it (let's ignore the 5mp for now as we focus on the exposure vs fov mystery). Thanks.

After numerous hours of testing. This is my finding. At daytime at 1/500 shutter.. 3mp and 2mp in the 4300s is almost indistiguisible. But indoor at 1/30 shutter speed, there is more noise (artifacts) in the 2mp setting of the 3mp. I think the explanation is this. When they do direct sampling of the 2mp (1080p) resolution of the 3mp full sensor. Do you think they just enabled the sensor pixels at the center (the 1080p part) or all of it? It's more likely they sample the entire 3MP then crop it in software to 2mp (1080p) but during the cropping and saving it.. there is more compression introduced resulting in more noise. I did dozens of saving and comparisions indoor. I can't share sample images now because they are on private property but anyone can try them (and to those who do.. please confirm it). Thanks.

MaxIcon. Any ideas why there are more noises in the 1080p setting of the 4300s than its 3MP resolution?

Before I got my first camera. I talked to the axis resellers/installers. He said china cameras have missing pixels and his axis cameras worth over 10 times have full pixels. I checked. It's not true. If only he said axis has 10 times better low light or DSLR like sensor signal to noise ratio.. maybe I could think twice. Also they sell the axis to government institutions with unlimited budget by bribing the officials (our country just few hours boat ride from China). He also told me they don't sell NVRs. Anyway. If I can buy a used axis from ebay. Would this run in the dahua or even Hikvision NVRs with full motion detection capability? Or need a computer (or pc based) to run it? Checking Axis website. They don't give sizes of the sensors. Buellwinkle review has it listed at 1/3".. same size as dahua.. but for it to really perform optimum at low light.. it has to be as big as DSLR or about 1 inch sensor.

If you don't care for the input from people who do this kind of work all the time, you do have a few other options: - Buy some different cameras and test them to see the differences for yourself. - Take the salesman's/marketeer's/website's word on which will fill your needs. - Put yourself in the hands of a professional and let them take care of it. The first way is the best way, but takes time, work, and money up front. On the upside, you learn quite a lot about cameras doing this, and don't have to rely on other people's advice. This is how most of the users here have learned about cameras, what works, and what doesn't. The second way is something many people do the first time, then never again. The third way is good if you choose your professional well, but you're paying extra for the years of experience they've gathered following the first path. If you choose poorly, you're back on the second path. 99% of installers in my country just install analog cctv and dvr. IP cams are so rarely used that almost all installers haven't directly compared any dahuas with hikvision. They haven't even hold one as I asked many. Also I live near China. And Axis camera replacement will take a month because it has to come from the US. And the one or two Axis camera importers said their Axis cameras are better because the cheap cameras have bad pixels not working. They don't know the meaning of dynamic range, etc. Poor country.

Just an update. I went to the Samsung service center and have the phone reflashed. Push notification can work now. Apparent some other applications caused conflict in between the two dual sims and some system disturbances. But for ultra security. It seems a separate GSM alarm dialer connected to separate PIR is necessary.. because if the robbers cut off the building power supply.. there NVR can't even send notification.. unless it is put on UPS.. but then you can't hide both NVR, UPS in hidden area to keep them off robbers. And even if UPS functions, they can see the red IR lights in the camera and may even return to you to get the evidence. So gsm dialer with battery backup seems the best solution for instant at the scene police action. But if anyone has other thoughts. Please let me know. In my country. 90% of banks don't have security guards at night. They rely on cctv and mostly analogs. No joke.

After a day of testing trying out all combinations which includes using port forwarding, buying 2nd iDMSS plus in an IPAD and borrowing another Samsung phone and buying 3rd gDMSS installing in that phone and borrowing 3 mobile sims and exchanging them in all kinds of combinations. I determined the problem is in my Samsung phone.. it is a dual sim grand 2. I'll let the service center reflash it and if not successful. Push notification may not be compatible with dual sim Samsung and i'll have to buy another phone. But then. I still need to get a backup GSM dialer.. because the monitored building is a bank and no one to watch it at night. So need to rely on cctv and motion detection and 100% transmission of that signal which GSM dialer can certainly do (and upon live view confirmation will deploy SWAT team to surround the bank building for engaging and apprehension of the bank robbers).

I have 2 units of the same NVR4204. And I have bought the paid android gDMSS with p2p access. I have 1 unit at home to experiment and another at a remote location. While I can view the NVR remotely. Push notification can only arrive if I was at Wifi. If mobile internet. Push notification can't be received. I don't know why. Maybe p2p and push can't be used if mobile uses 3G and not Wifi. But note I can connect to the nvr remotely and adust setting such as enable Push Notification even in mobile internet. But it can't receive it. I also done experiment and have my home nvr (same model nvr4204) in front of me manually triggering the alarm input.. and just the same.. if the phone is in mobile internet. It can't receive it just like the first nvr. Again if I use wifi at home and my remote nvr detect something remotely. I can receive Push notification. If anyone knows the solution to this deep mystery. Please let me know.