MaxIcon
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Posts posted by MaxIcon
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Here's an inexpensive 25mm lens I use on a Hik 2032 for plate capture:
It's 1/2", so you get more zoom than you would with a 1/3" 25mm, which is a good thing. It's not a great lens, and has some chromatic aberration, but is decent overall. Changing lenses is a pain on the 2032, so be sure to focus it at the right location while it's apart.
I had to use slightly longer screws to install my sensor board, as the lens is just a little too long and touches the end glass before the board is seated, but it's held up fine over a number of months. Because of this, you can't fit any longer lens on this camera without some major mods.
Mine works fine in daylight at about 80-100'. Once the light drops much, the image quality drops as well, and you can't read plates any more. The cam's IR is nowhere near strong enough for that distance.
To get an idea of what you need, save a snapshot of the cam at full resolution with a plate in view. Open it a paint program, and see how many pixels wide the plate is. A US plate is 1' wide, and you need at least 60 pixels per foot to get a decent image for plate recognition.
As 1Diesel pointed out, you have a lot of angle there, so the actual plate width is less than a foot, but you need more pixels per foot in this situation, so the same measurement is meaningful, even though the plate image isn't a foot wide.
The full screen image you posted is about 950 pixels wide, and the plate is about 25 pixels wide, so that's 2.6% of your horizontal resolution. It looks like the plate is about 20 pixels wide in the full screen shot, but it's hard to say what the NVR is doing to the image.
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Often, you need to connect to a wired switch or router to set up the wifi on the camera. You'd select the SSID of the wifi network, any other options like encryption style, and put in the password. Once that's done, you can disconnect and see if it connects to the wifi. You'll also have 2 IP addresses for the camera; one for wifi, one for wired.
There are push-button solutions to wifi connections, but I'm not familiar with them. User-friendly wifi gear like Arlo and Dropcam don't have wired connections, and have a way of hooking up without them, done by following the instructions with the camera.
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The two best bets for a low-cost PC based NVR are Blue Iris, which is inexpensive and very capable but requires a powerful PC, or Milestone Xprotect Go, which doesn't need as much CPU but has limitations on the number of cams and record time.
After those, it's mostly a per-cam license fee, and there are a variety of options depending on your budget.
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Amazon has a variety of PIR sensors listed, from components to system level.
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I think there are other ways, but the method I use is this, using Wireshark:
- Connect the cam directly to a PC (or through a dumb switch) with no other network connections.
- Start up Wireshark. There should be no network activity.
- Reset the camera and wait while it boots.
- Wireshark should show a variety of messages, and one or more will be similar to one of these. The XXX address is the cam's current address:
“Gratuitous ARP for XXX.XXX.XXX.XXX”.
“Who has XXX.XXX.XXX.XXX? Tell 0.0.0.0”.
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It would help if you posted a screenshot of what the problem looks like.
Typically, this will be dropped frames causing ghosting, where there are several frames worth of the moving object all shown together. You might try reducing the bit rate to see if it helps.
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I mean how to compute a bullet camera power usage if powered by such researchable lead battery. For instance, the bullet camera is 5 watts.. does it consume 5 watts for one sec, one minute or one hour? Anyone?
If a camera uses 5W, it does that as long as it's on, so 1 hour of operation would be 5W-hr.
Battery capacity is rated in amp-hours. 5W at 12V uses 0.4A (5/12=0.42).
A battery rated at 7Ah will supply 0.4A for 17.5 hours (7/0.4 = 17.5).
It's a little more complicated than that in real life, as the voltage drops steadily during that time, so you'd need to test it to be sure, but that's the ballpark answer.
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Dropcam and Arlo both record to the cloud, but only to the cloud.
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Tough to tell without doing network speed tests, and not just transfer rate tests, but more detailed ones. I don't know what's available for that outside the corporate network market.
I'd guess the NVR's internal switches are optimized for connectivity to the rest of the box, but you never really know with Chinese gear until you try it. Some very similar NVRs can have pretty different performance, even with identical hardware, due to software differences.
Not many people complain about the cams going briefly offline due to network signal drop, in general, whether they're using internal or external POE. When they do, it's often tracked down to an external component.
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Good point - that's probably the best bet for good power capacity and easy charging, though starting to get bigger.
14.4V is more common than 12V for power tools, and I bet most cams would run fine on it. There's some risk you'd burn it up, but may be worth a try...
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It says it's a day-night camera, which usually means a movable IR filter, but it's always good to check if they don't say that specifically.
ETA: It specifies ICR, which is IR cut-filter removal, which means it does have a movable IR filter.
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Running different battery types in series can be tricky, as the current will be limited by the battery with the highest internal resistance, but it's easy enough to test. You won't get a lot of current out of a setup like that.
That said, most 9V batteries contain 6 1.5V AAAA batteries, so you can probably do it with no problem.
http://www.instructables.com/id/how-to-open-a-9v-battery/
A 9V battery typically can supply around 500mA, for 4.5W, which is enough to run many cams. It will only last an hour or less, depending on exactly what brand and type you buy.
You'd be better off with a set of 6 AA batteries in a holder - more current, more run time, not much bigger. A good quality set of AAs will run the same 500 mA (6W) for more like 2-3 hours, depending on how low the voltage can get and still operate the cam.
Here's the smallest 12V battery I know of - the A23. Not much current capability, and probably not enough to run your cam for long, if at all:
I don't think they're available rechargeable, but who knows these days?
If you want anything more than couple of hours, you'll need a motorcycle style lead acid battery.
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Yeah, quality will always be a factor, especially in low-end switches, since it all depends on both the hardware and software quality. Like with cams, better to go with a name brand that others have had good results with.
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Hik's published a guide for IR bleed problems on the dome cams:
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Btw.. external IR illuminators sold locally can only work with the analogs ccd.. anyone got a clue why the IR illuminators is invisible to the IP cmos?The other thing being sold locally is something smelly... Someone's yanking your chain. IR illuminators work fine with IP cams that have movable IR filters.
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I also inquired about their IR illuminator.. they said it's only for their ccd analogs.. anyone know why it won't work on an IP cmos camera? What is the IR range in the sensors between the analogs and ip cams and and/or between the cctv ccd and cmos? Anyone got a clue?IP and analog sensors tend to have the same IR sensitivity, and 850nm IR is the standard. The main difference is whether the cam has an IR filter or not.
Many tiny cams have a fixed IR filter, so they won't see IR at all, and daytime colors are correct. Some have no IR filter, and will see IR, but daytime colors may be off since it's not filtered out. Most regular size cams have movable IR filters that switch in for bright light and out for low light. Generally, any cam with a movable IR filter or no IR filter will see an external IR illuminator.
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Those TVL settings are just ordering codes for the lens size you want. They aren't actual TVL numbers. TVL is a resolution spec (much abused), and isn't used for IP cams in general.
So, if you want wide angle, you'd order the 380TVL, which would get you the 2.8mm lens.
Generally, you'll get full frame rates at 1080p and lower frame rates at 3MP. The Hiks have a smaller horizontal FOV at 3MP than at 1080p, which is unusual, but that's the way they roll.
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A 1/4" sensor will show the equivalent of a longer lens, compared to a 1/3" sensor. The lens shows the same image circle to each sensor, but the smaller sensor covers less of the image, so will look like a longer lens was used.
There's a formula for figuring this out; I'll see if I can dig it up.
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Of the starter level cams, the turrets have the best IR. Domes can have IR reflection problems, and more people are moving to turrets to avoid this. Strong IR can wash out stuff up close, and smart IR isn't always effective at controlling this.
The mini-bullets are smallest, but can be knocked around more easily, while some people like the looks of turrets better.
Lens size is always a trade-off between how much you want to see and how much detail you get. This is where getting one of each will help figure out what works and where. If you need to zoom a bit to get closer to something, 6mm is good, but most people start with shorter lenses and only get 6mm for specific areas where they need it.
The 180 degree cams can be tricky. They give a great field of view, but not much detail, and the stream needs to be de-warped to get rid of the fisheye distortion if it's a single-sensor cam. If it's multi-sensor, there's more bandwidth used, but better detail from each sensor.
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The sweet spot is a POE switch with 100Mb ports and a Gb uplink port. As Boogieman says, 100Mb ports are fine for cams, and all Gb POE switches are still expensive.
Even running 8 ports at 4096Kbps won't load down a 100Mb uplink, but I always like to have overhead, so a Gb uplink port will handle future needs.
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Placement for a front door cam is usually a trade-off. If you mount it above the door, you're too high when they're right there, and you don't get as good a view. Down low, and the physical security for the cam isn't as strong, if that matters.
My door cam is mounted to the side; in your pic, it would be above the window to the right of the door. This gives a pretty good view (I went with a longer lens; 6mm, I think) and isn't as noticeable.
You get side view, and that can be a bit limiting too.
Best bet is to come up with a way to temporarily mount the cam in each location. I like to use a ladder and towel with bungee cords; the towel lets you redirect the field of view easily.
This lets you test it in a variety of positions and figure out what works best for you.
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If the coax is exposed, you might want to wrap it with coax seal or self-fusing tape.
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It's not easy to find high quality megapixel IR compensated M12 lenses for a reasonable price. You can get great ones that are very expensive from places like edmund scientific, but these are usually well over $50.
I've had good luck with m12lenses.com. The quality is decent and the price is reasonable, if not cheap. You can get cheaper lenses on ebay and dealextreme, but the quality tends to be poor, and you never know what you're getting until they arrive.
At m12lenses, be sure to pick the 1/3" category (assuming that's what you have), as 1/2" lenses will give a different FOV than the same size in 1/3".
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The D-Link is unmanaged, so it won't do anything with IP addresses but send them along.
It sounds like you need to plug the D-Link connection into the LAN port on the NVR, not the camera port. I'm guessing the camera ports on the NVR aren't generic network ports, but are dedicated to single cams, so the cam port 1 only shows you a single camera.
I'm not familiar with the NVR, but here's what I'd try, assuming there's only 1 LAN port on the NVR:
- Connect the D-Link and the NVR LAN port to your main network switch or router. This may require changing the camera IP addresses to match your main subnet, as the NVR often uses its own subnet settings.
Someone who runs an NVR like this can say for sure what the best way to connect is.
Avigilon 4K - Sample image
in IP/Megapixel Cameras and Software Solutions
Posted
The 4k low light image looks pretty good. There are a lot of sharpening artifacts in the dark areas, but where there's a bit more light, things look better.