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Cortian

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Posts posted by Cortian


  1. 41 minutes ago, clementsj said:

    Gigabit ethernet over cat6 has a max distance of 295' although we have a couple PTZ's at 325 that seem to work ok.  I agree with jeromephone.  Use another poe switch instead of an extender and you should be fine.

    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.


  2. 23 hours ago, jeromephone said:

    We always just used a laptop and a poe source.  

    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.


  3. 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.


  4. 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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  5. 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.


  6. 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.


  7. 1 hour ago, tomcctv said:

    yes This is why it’s banned in USA ..

    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."

     

    1 hour ago, tomcctv said:

    countie would not need to ban if it was as simple as firewall ....

    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.


  8. 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.

    3 hours ago, Sir Lenscelot said:

    And your welcome to have my IP information and logins if i felt the need to install them, However it would do you no good as my network would be secure with a properly configured, good quality firewall. You know the kind that actually can be deemed a firewall which protects all directions. 

    Indeed.  Even I can't get directly to my IP cams from outside the LAN.


  9. 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.


  10. 5 hours ago, tomcctv said:

    Wow ... what did you say you used to do and I did say don’t compare photo cameras 

    but your not doubling the pixel size.... your adding more pixels into the same area ....... pixels we need to temp call them information for you to understand

    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.

     

    5 hours ago, tomcctv said:

    and don’t you call pixels big or small let’s say more and less  to keep it simple  

    Tom, the pixel size directly relates to its light sensitivity.  That's the whole point of this discussion.

     

    5 hours ago, tomcctv said:

    pixels are information the more there is the better ....

    Provably false.  (I've already explained why.  I'm not going to repeat myself.)

     

    5 hours ago, tomcctv said:

    starlight which is a complete different sensor and developed by dahua and now licenced out the everyone ...

    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.

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  11. 1 hour ago, tomcctv said:

    DIYer questioning a company owner both Europe and USA ...

    A "DIYer" with backgrounds in both hardware and software design and who was once a Senior Software Designer in the vision inspection systems industry.

    Oops?

    As to your "there is no such thing as big or small pixels" assertion: If that were true, then for every doubling of pixel count they'd have to double the image sensor size.  That would, in turn, require increasing the size of lenses to make up for the light loss otherwise incurred in spreading the same light over double the sensor space.  The sheer cost increase in fabricating them (the bigger the lens the harder to fabricate w/o various distortion artefacts) would make high-megapixel cameras prohibitively expensive.  Obviously the lens on an 8MP camera isn't four times the size of that on a 2MP camera.  (In fact I expect they're using the exact same glass on both.)

    In any event, your assertion is provably false, as evidenced by Sony's STARVIS CMOS sensor specs: CMOS Image Sensor for Security & Surveillance.

    The Dahua Starlight camera I recommended uses a Sony STARVIS CMOS sensor, which I'm led to understand is regarded as the best low-light sensor in the industry.  So, unless Dahua's degrading the performance of those fine sensors in their software or with inferior glass, Dahua cameras should perform as well as anybody else's using the same sensor.


  12. 1 hour ago, tomcctv said:

    Ok all manufacturers must be wrong ......why would they ever need to go up in resolution if it does not work so selling 29mp cameras is now pointless

     

    2mp is old ....... Hence why we have 5mp and 8mp recording NVRs 

    does not matter how you put it high resolution is better 

     

    it as grow from CIF - 4cif-D1 -1.3mp and up ...... And always been about data in a pixel ..... More information the better

     

    which was the last 5mp camera you installed and 2mp was better day and night ?

     

    The manufactures aren't all wrong, it's just that "pixels sell" and bigger isn't always better.

    E.g.: When my wife and I were getting set to take a vacation in Europe last year I spent more than a few hours qualifying a good camera that would be the best compromise between being easy to haul around and having acceptable image quality under varying conditions.  No matter how many times I found myself trying to go for more pixels: In test-after-test and comparison-after-comparison the Panasonic Lumix DMC-FZ300, which had a comparatively "low" pixel count, kept winning.  Why?  In part because of its low-light performance.  Compared to cameras with twice the pixels or more: It captured higher-quality images, with much lower noise, in challenging lighting conditions.  All the pixels in the world don't matter if the image is buried in noise.

    Wasn't the most expensive camera in its class, either.  Heck, the macro lens for my Canon body cost twice what that glorified P&S camera did.

    So, while "2MP is old": "Old" does not necessarily equate to "worse."  It's been proven, time-and-again, in real world tests and installations, that nothing beats a 2MP Startlight camera in low-light.

    That being said: I, personally, have no experience at all in this field.  Something to which I've admitted several times.  My opinions are based upon the reviews, opinions and tests of others.

    Some of those others, btw, are experts in their field.  Some of them are relatives of mine that operate a highly-successful surveillance systems company.  They concurred with my findings: That, short of cameras costing 3-5x more, nothing beats the Dahua Starlight cam I chose for outside use in low light.

    "Better day and night" was not my assertion.  We're talking solely about low light performance.  (It's in the thread topic.  As is his desired price point.)


  13. 7 minutes ago, alpalp said:

    So it is a Dahua for me then. Great! Thank you Cortian!

    I remember you recommended Dahua IPC-HDW5231R-ZE 2MP, what other models is good you think?

    You're welcome.

    I'm new, very new, to this, myself.  So I cannot in good conscious recommend anything, per se.  All I can do is share the decisions I've made, so far, based on my own research.  To that end: If you're looking for an outdoor, low-light PoE IP cam: The one camera is my only suggestion.

    I'm sure they have other 2MP Starlight cameras in other form-factors.  I would only suggest you probably want to avoid domes for outside use, as they get dirty and the plastic gets degraded by UV, both of which lead to fogging the image.


  14. If you're looking at stairwells, which tend to be long and narrow, I don't know as 2.8mm is what you want.  The FoV you need will be very narrow.  With a 2.8mm lens you may be wasting a lot of pixels on looking at walls.

    For relatively unobtrusive cameras perhaps you want to look into ones labelled as "mini-dome"s or "wedge"s.  E.g.: For our family room I chose the  Dahua IPC-HDBW4231F-AS 2MP Starlight Mini Dome with a 3.6mm lens.  I chose that lens because the camera will be corner-mounted and it has an 87° horizontal FoV, which is about as close to perfect, for my application, as can be.  The 6mm lens on that camera has a 51° FoV, which might do well for stairwells and hallways.

    The other way to go is a camera with a motorized, or otherwise adjustable, lens.  Then you can optimize it in-place.

    Reasons to consider domes for inside use?  Well, to me, they look less intimidating :)  (Particularly the little Dahua mini-dome I have sitting here.)

    Why do you want either no IR or to turn it off?  True, when somebody's going up/down the stairs they'll probably be lit.  The key word there being "probably."  No need to unnecessarily hobble yourself, IMO.

    There are many brands.  I like Dahua.  @tomcctv dislikes Hikvision with a passion :), whereas my security professional relatives in Europe love Hik.  There are others who won't used Chinese-made cameras on a bet.

     


  15. 43 minutes ago, alpalp said:

    Are you the only person in this forum :( Why so little activity here?

    5 threads? You mean other people asking the same thing? I will try to search, thank you!

    They told me 2MP is better than 5MP on the starlight, do you think that could be true?

    Thank you

    @tomcctv isn't the only member here, but he's one of the most active.  He's probably also one of the most knowledgeable.

    As to why there's relatively low activity, here?  I do not know.  Stick around.  Learn.  Eventually contribute.  Then there'll be more activity here :)  Speaking of which...

    I don't know about five threads, but you've started at least four on the same subjects.  Please pick one thread and stick with it?  (Except the one that got locked.  Let this be a lesson in on-line forum: Don't get into battles with trolls.)

    For low light applications 2MP is "better" than 3, 4, 5MP or more because less pixels == larger pixels == better light gathering/sensitivity.  If you examine, for example, two Dahua Starlight cams that are otherwise identical, except one (the one I previously recommended to you) is 2MP and the other 4MP, you'll find the 2MP has much better low light sensitivity.

    The other reason bigger pixels are better than smaller ones in low light is a property known as SNR: Signal-to-Noise Ratio.  For a given level of light, in a low-light environment: Bigger pixels will have a higher SNR than smaller ones.  This explains why a 2MP Starlight camera can appear to the the same, or better, resolution than a 4MP camera in low light: Because the 2MP image has less noise.  Noise destroys definition.

    If you know you're always going to have plenty of light, then, by all means: More pixels is nearly always better.  But in light-deprived settings: Not so much.


  16. I'm sorry, alpalp, but I do not have a recommendation for you.  Some of the more experienced guys here I'm certain might have.

    A lot of people like BI.  Maybe it's great.  But I don't trust MS-Windows any further than I can spit, so I'll never know.  If one of the Linux flavours is your thing, possibly Blue Cherry DVR?   I may give that a go if things don't work out with Synology.

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