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Cortian
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Cortian last won the day on March 30 2019
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Elettroincasa71 started following Cortian
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"Really good night vision" and "cheap" are mutually exclusive. E.g.: My 2MP Dahua Starlight cams were $165 apiece, and that's already considered "economical" for a good low-light security camera.
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IP camera does not work after 100m
Cortian replied to RonZ's topic in Installation Help and Accessories
1000BaseT, aka: "GigE," has a max length of 100 meters, or 328 feet. Beyond that you've exceeded the 1000BaseT spec. Nearly doubling it is guaranteed to fail. Beyond 100m you need to create a new collision domain, which requires a switch or Ethernet repeater. And power may be part of the issue. The longer the run the greater the voltage drop. Too much voltage drop for the load and there won't be enough to run the device. -
Can't get much simpler than that. For my runs at home I put a Klein Tools Scout Jr. on a newly-installed cable to make sure the wiring is right, then fire up iperf3 on server and laptop to make sure it's really right. Then I simply hook the camera up, configure it into the NVR and have done with it. If I had buckets of money or was doing this for a living, I'd have a Fluke cable tester that would do parts 1 & 2 in one go.
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PoE cameras power issues with Swann. Is there better?
Cortian replied to jrmull's topic in IP/Megapixel Cameras and Software Solutions
Obviously, if nature and the wildlife are destroying your cables, nothing you do with your NVR, PSU or cameras is going to do much good. So the first order of business would be to protect those cables that need protecting. UV-resistant PVC tubing should do, I would expect. As for the 48V PSU: I can't imagine somebody doesn't make one that's capable of supplying more than 2A. The question then would become is the NVR capable of handling it? I've no way to know. Personally, I am not a fan of single-vendor solutions--for anything. That includes surveillance systems. Sure: I'm probably giving up some bells and whistles by mixing-and-matching, but I've got the basic functionality I need and that allows me to select the best hardware that suits my needs, as determined by me, rather than what a particular vendor or manufacturer decides is best. An example directly applicable to your issue: If the NetGear PoE switch I've chosen proves inadequate, I can replace it either with a bigger NetGear PoE switch, or one from another manufacturer, w/o any impact on anything else in the system. -
There's nothing you're going to put at the top of a 30' high metal pole that's going to protect electronics from a nearby lightning strike, much less a direct strike, if that's your concern.
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Often it's not the cost of the cable, but the cost or difficulty of running it. That was why, when I did new cable installations for my employer, I always ran 25-50% more runs than the projected need. (And, when they recently switched from a legacy phone system to IP phones, it still wasn't enough. But they only had to add a dozen or so new runs, so not bad for a 20-year-old install with close to 500 runs ;).) Terminating existing cable is inexpensive and trivial. I'd terminate it, try it, and see if it worked. If not: Then replace it with Cat5E or Cat6.
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Can't go 900 ft. with twisted pair Ethernet without powered repeaters. Max is 100 meters (328 ft.). And even that may be pushing your luck with PoE, depending upon the load.
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Define what you mean by "HD," please? Technically speaking: "High definition" is 1280x720 or better. That would be a 2MP camera. Secondly: As resolution (megapixels) goes up, light sensitivity drops and noise increases. Thus, in low-light conditions a lower resolution camera can out-perform higher-resolution one for image detail. Search on it. There are plenty of real-world examples. As an example of sensor megapixel count vs. light sensitivity, consider the specs of two otherwise identical cameras: The Dahua IPC-HDW5231R-ZE (2MP): Minimum Illumination: 0.006Lux/F1.4 ( Color,1/3s,30IRE), 0.05Lux/F1.4 ( Color,1/30s,30IRE) and IPC-HDW5431R-ZE (4MP): Minimum Illumination: 0.03Lux/F1.4 (Color,1/3s,30IRE), 0.3Lux/F1.4 (Color,1/30s,30IRE) The 2MP camera has five times the light sensitivity at a 1/3 sec. frame rate and six times the light sensitivity at a 1/30th sec. frame rate. OTOH: If you're relying on IR illumination it's not such a big deal and more megapixels may be advantageous for you. The other thing you may wish to take into account is your display capability. It boots nothing to have a 4K camera and a non-4K display. The camera may see the detail, and the NVR record it, but the display won't render it, so you won't see it.
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They're to be banned for use by government agencies and, I would expect, private businesses performing sensitive work for government agencies. They're not banned outright. However: This is a black eye for those manufacturers. Many companies will look at this and think "If it's not good enough for the government, it's certainly not good enough for me." I wonder if any non-Chinese tech firms will see this, realize they're being presented with a tremendous gift, and jump to take advantage of it? Btw: As far as we know, Dahua was simply guilty of poor security practices, as opposed to actual intentional nefarious activity. This is why I'm willing to give them a pass--with safeguards.
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Which security camera to purchase?
Cortian replied to Chris6700's topic in General Digital Discussion
Just adding a 3rd vote to Tom's and SL's. (With the exception of SL's comment, re: WiFi. Yes: Wired is way, way better. Particularly with video streams and when we're talking security systems. But a good WiFi system [most are crap] can work just fine, IME.) -
That's a bit inaccurate. Hikvision (and Dahua I believe?) are banned for use by the U.S. government. (And, likely, by US Gov't contractors and others with sensitive US Gov't contracts.) They are not "banned in the USA." Nobody's suggesting a firewall should be one's first line of defence. Egress filtering on a firewall's there in case other measures fail. E.g.: I would not buy and use Dahua cameras were I not relatively satisfied with Dahua's explanation of what happened and their assurances they've addressed it. My LAN and Internet border security measures are just in case they're misleading me, after all, or for potential future issues. That being said, and I meant to address this in my earlier comments, but forgot: The measures I've taken are well beyond the capabilities of the average (read: consumer) Internet user. What should really happen is Internet border routers should be configured for security stances similar to what I've described out-of-the-box. Problem with that is: Then a lot of plug-and-play IoT things would be difficult to get to play. It's the same reason MS-Windows was was so easy to compromise for so very long. If Microsoft had made it half as bullet-resistant as they should have: It in all probability would not have achieved the wide acceptance from non-techie end-users it did. So: Manufacturers are damned if they do and damned if they don't. On the gripping hand: Shunning Hikvision because the U.S. Government (or whomever) suggests they're a threat doesn't solve individuals' network security problems. Anything consumers (and, by "consumers," I mean all consumers--residential, business and government) install on their networks, particularly IoT devices, can be a threat.
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Sir Lenscelot has the right of it. Proper firewalling consists of both ingress and egress controls. The default policy on the most effective firewall is "That which is not explicitly allowed is denied." That is somewhat impractical, taken to its absolute, wrt egress filtering, but you can take measures to limit your exposure. E.g.: The only device on my LAN that's allowed to make outgoing connections on port 25 (SMTP) is the home LAN server. That way, even if a desktop, laptop or IoT thing does become compromised with a spam-generating Trojan, it isn't getting anywhere. For my cameras: I've put them all into a particular subnet and blocked that subnet for all outbound traffic. (Inbound connections are always default denied.) Soon I'll acquire a managed switch for our LAN's "backbone." I'll implement VLANs and one of those will be a VLAN for only IP cameras. The border router will prohibit connections from that VLAN. That way: Even if some camera comes with malware pre-loaded, malware that's smart enough to come up with its own legitimate IP address that's not blocked by the border router, it isn't getting anywhere. In fact: All IoT stuff is going on isolated VLANs like that. Not only will that stuff not be able to get to the Internet, but it won't be able to get to Other Stuff on the LAN to which is does not need access. The only reason I didn't already have a managed switch is, until recently, it hasn't been particularly necessary. Now, with all the IoT stuff, it is. Indeed. Even I can't get directly to my IP cams from outside the LAN.
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Lost My Camera's IP - Help?
Cortian replied to abrogard's topic in Video Transmission/Control Devices
Probably when you plugged the camera directly into the NVR if was given an address on a completely different network, which is why nothing on your network can see it. I don't know if Dahua IP cams have an external factory reset switch, but, if so, that's might be what you need to do. It might be the NVR gave it a dynamic IP address with a long lease, in which case your camera will eventually ask for a new address on your LAN. No way to know how long that will be. Could be quite some while. -
Best low light vision IP camera, budget 200USD?
Cortian replied to alpalp's topic in IP/Megapixel Cameras and Software Solutions
What I did for a living once-upon-a-time was design software for machine vision inspection systems, so I know just a little >< about how photo imaging sensors work. And, yes, digital camera photography is one of my lesser side-hobbies, so I know something of how that technology works, too. You can insist that photographic cameras not be brought up, but that doesn't change the fact they use essentially the same technology and are guided by the same laws of physics (as we currently understand them). "your [sic] adding more pixels to the same area...": Bingo! And more pixels in the same area means the pixels must be smaller. QED. Tom, the pixel size directly relates to its light sensitivity. That's the whole point of this discussion. Provably false. (I've already explained why. I'm not going to repeat myself.) It is? Please show us the ™ or ® mark on Dahua's use of the term "starlight." Please show us where Dahua's technology licensees are acknowledging the use of Dahua's patented startlight technology. You cannot, because "starlight" is a generic term for imaging sensors and surveillance cameras that perform better than others in low-light conditions. This is evidenced, for example, in this Bosch press release: Bosch introduces latest starlight technology - The ultimate 24/7 IP video surveillance cameras just got even better, where "starlight" is mentioned with no attribution. And Dahua is using Sony STARVIS sensors, as demonstrated, for example, by Dahua DH-IPC-HDW5231R-ZE - 2MP WDR IR Eyeball Network Camera and other Dahua Starlight products which also prominently mention using Sony STARVIS technology. I'm not going to argue this with you any longer. I have design background, technology experience, facts and documentation on my side. You have beliefs based on what is apparently an incomplete understanding of the technology, which is now leading you to contradict yourself.