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Ok, here are some license plate comparisons between the Dahua HFW3300C and the Hikvision/Swann 1080p SWNHD-820CAM cams. Let me know if there are problems with any of the uploads, as keeping this stuff straight is a bit of a challenge! Likewise, any feedback on my misassumptions is good. I'm not a license plate capture expert, so any thought from those who have done it with inexpensive cameras would be great. Both are set at 1080p, and the Dahua is zoomed in to 3.3mm (widest angle), which closely matches the Swann factory lens. Both are in auto day/night mode until the forced day mode clips. The cameras are perched atop a 6' ladder, so they're not quite as high as when mounted under the eaves. I used my 2004 Miata, which has non-halogen headlights and a non-illuminated front plate. I pulled in from off camera, pulled into the driveway, and backed out again. Since both cameras are on at once, the night mode shots have IR on from both cams, and you can see the effects of the different responses of the 2 cameras to changing light conditions: - The Hik drops into day mode more readily than the Dahua, which switches off its IR. On some of the Dahua shots, you can see the IR brightness on the license plate change when this happens. - The Dahua rarely drops into day mode, but its IR is independent of mode, and is strictly controlled by the photosensor on the IR board, so it'll switch on and off as the headlights get closer and further away. On the Hik shots, you can see the IR switch on as I back out of the driveway, lighting up the plates more (and usually washing them out). I took a lot more clips than this, with a variety of WDR settings (for example), but these are the best examples of each mode on each cam. Overall, there are a few general conclusions from these tests regarding using these for night license plate capture: - WDR was useless in night mode. More expensive cameras have better WDR, and it may be better in day mode. When I get time, I'll test this. - HLC on the Dahua was useless in night mode. This should be what HLC is good at. - BLC was marginally useful, but the response times on these inexpensive cameras to dynamic lighting changes is too slow to guarantee useful captures in fast moving situations. - IR did more harm than good, again due to the poor responsiveness. So, to use an inexpensive home camera for capturing license plates, you need a few conditions to get any kind of decent results: - A good choke point. The driveway is the best possible, as you can be sure exactly where the cars will be. These camera locations would be useless for cars parking on the street, or pulling in across the street. To get street caps, you'd need cameras pointing up and down the street, zoomed in on the street width. This will depend on your home's layout, of course. - A lens zoomed in on the choke point to get the pixels per foot needed. With these 3.3mm settings, even when the exposure's good, the resolution has dropped enough that a plate at the end of the driveway is not very readable. Zooming in to cover just the driveway would be a big help here, allowing both better exposures and better resolution. The Hik's lens is glued in, so it's not optimal unless you want to hack it. When I do the next round of tests, I'll zoom the Dahua in and test this setup. - Fast enough exposures to avoid motion blur, though a car in the driveway would need to slow down, stop, and back out, so there would likely be some good frames. This would matter more with street captures. - Fast enough response to changing lighting to avoid washout from headlights or IR reflections on the plates. My Vivotek switches in and out of night mode much more quickly than either the Dahua or Hik, so it may give better results, especially if the car's lights are off. - Lighting to ensure the plate's illuminated. The daytime mode gave the best views by a long shot, but if the car's lights were off before they turned into the driveway, the images would likely be too dark. I'll test this in the next round as well. Some cars have plate lights front and back (and some states don't require front plates, of course), some cars have much brighter headlights, and in general, lighting is unpredictable.. Buellwinkle posted some suggestions for reliable license plate capture, which include expensive IR and more specialized cameras. I believe a home camera can give decent night time plate capture if the settings are tweaked for the surroundings, but like all night performance on inexpensive cameras, there are trade-offs that more money can take care of. Anyway, on to the clips! Here's the Hik, blc enabled, set for "down": The Dahua, blc enabled, driveway selected for blc: And the Dahua, hlc enabled on medium. The Hik doesn't have an HLC setting: Next, the WDR settings. Here's the Hik, WDR set at 50. Higher WDR made the image noiser, and lower had less effect. It wasn't much use at any setting: And the Dahua, with WDR set at medium. Again, not much use on any setting: Next, the clips that finally look like they're going to be useful! I tried some fixed exposures, as high-speed fixed exposures are used sometimes with powerful IR illumination, but they weren't as good as leaving them in auto exposure. I adjusted the gain so both cameras were about the same when no cars were present. Turning the gain up towards 100 increased the noise quite a bit and made the plates harder to read as a result. Here's the Hik, day mode, auto exposure, gain at 68 (to match the Dahua at 50): And the Dahua, day mode, auto exposure, gain at 50: For the rear plate checks, I set it fixed at 1/30 second, 50 gain, day mode, and backed in to the driveway, to see how it handled the different lighting of the rear end. I'll check this again on auto exposure, but it should be good. Here's the Hik, backing in: And the Dahua, backing in: This is the kind of thing the manufacturers should be posting on their websites, but you can see why they don't from these results.

That 12W PS should work fine. 2 things to watch for: - The plug needs to be 2.1x5.5mm - Positive needs to be on the right connector. I believe the center is positive, but you'd want to verify that. I use these connectors for quick tests and simple hacks: http://www.ebay.com/itm/5-Pairs-2-1mm-x-5-5mm-Female-Male-CCTV-DC-Power-Plug-Jack-Adapter-connector-/271340939179?pt=US_Surveillance_Cables_Adapters_Connectors&hash=item3f2d2e27ab#ht_1279wt_896

What type of artifacts? Are these lost frames causing ghosting and such? My 3300C had a lot of trouble with ghosting/pixellization and dropouts, and 2 things got rid of the problems: - Running lower bit rates - Setting the i-frame the same as the frame rate (default was 2x the frame rate) Before, I had to run at under 2048 kb/s at 3MP and 10 fps. Once I set the i-frame to 10, I could turn the bit rate back up to 4096 with no problems.

Not all cams see IR. Many have a fixed IR filter, either over the sensor or attached to the lens, to keep the colors correct in sunlight. Others, like the older YCams, don't have a filter at all, so sunlit scenes are purplish, but they see the IR at night just fine. Cams with movable IR filters switch between day and night for the best of both worlds, with the cost and reliability hit of more moving parts. Any camera that sees IR will see it from a source away from the camera, just like with visible light. The benefit is that the IR doesn't illuminate the spiders/bugs/whatever right in front of the camera - they're still there, but they're not all lit up, so less likely for motion detect to see them.

The 3300C, and the 2100N as well, have problems with really soft compression in the shadows if you've got a mix of well-lit and shadow images. Hard to say if they'll ever fix that with firmware, since they never say what's in the firmware updates, and firmware can be hard to find. Vari-focal lenses are generally not as good quality at the extremes as fixed-focus lenses, but it totally depends on the lens. You can't adjust these over the network - they're strictly manual. In addition, some Dahuas have issues with the focus shifting when they're in the sun for a while. One of mine does this, and another user was posting with similar problems. I've given up on Dahuas, personally, but other people still like them.

I'm not sure I've ever seen a CS mount lens for a 1/4" sensor, but there must be some out there. More likely, you'll find mostly 1/3, some 1/2", with the occasional 2/3". You definitely don't want one designed for a smaller sensor, as BW says. If the lens is designed for a larger sensor than what you have (most box cameras today are 1/3", with some 1/2" available for more money), it'll have the effect of having a longer focal length and a smaller aperture. That is, a 50mm 1/2" lens on a 1/3" sensor will act more like a 70mm lens, and an F1.6 will be more like an F2.0. Actual results may vary! You can't control the iris manually, at least not easily. Auto-iris can be difficult to disable, depending on the lens design, and most auto-irises close when there's no power applied. Some you can remove the iris assembly with no problem, others need to be glued into the open position, and that can be either easy or hard. If the camera supports auto-iris, you can sometimes set the iris manually and just leave it, which will prevent any noise (electrical or audible) from adjustments, but that depends on the camera software. MP ratings are due to both lens element material quality, as mentioned, and coatings that control where the wavelengths focus, similar to the IR corrected lenses, but applying to all the different visible wavelengths. If red, blue, and green focus on different adjacent pixels or different planes, you get a fuzzier picture than if they all focus on the same pixel. I don't see any reference to day/night in the brochure or on the web page: http://www.fujifilm.com/products/optical_devices/pdf/cctv/security/varifocal/dv10x7b-sa2_e.pdf http://www.fujifilmusa.com/products/optical_devices/security/vari-focal/standard-series/dv10x7b-sa2l/ It looks like a good lens for the money, but it's always a gamble whether it will work for your app without trying it. You can find manual lenses, some new, some used, by searching ebay for 50mm lens cs, and other variations. The new ones under $50 will be suspect quality, but may work for your needs, while the used or NOS name brand lenses will be better quality, but limited quantity. Tamron and Rainbow are decent quality brands, too, though Rainbow is getting a little iffy.

If you google HDCP stripper, you'll see lots of discussion on this, as well as links to gadgets that work for some people.

That's what I would do (and have done) as well. You can get great deals on ebay on decent quality used CS or C mount lenses. Aside from Fujinon, seach on Computar and CBC (same brand) as well. Note that most of these aren't going to be MP lenses, but that's probably not an issue. Likewise, many aren't IR corrected, so if you focus them for IR, they'll be out of focus for white light, and vice versa. Finally, there are auto-iris and manual iris lenses. The one BW linked to is auto-iris, and the camera needs to support auto-iris to use this (most box cams do). You can remove the auto-iris assembly on some lenses, but this is unpredictable until you get it.

One potential issue when focusing very closely is that M12 lenses focus by screwing in and out of the lens adapter. If focusing at a short distance requires screwing the lens further in, you might hit the IR filter assembly before it's focused, even if it's OK at longer distances. There's no easy way to tell this without trying, and it would vary from lens to lens. This is where a box cam with a CS mount lens would be better. CS lenses focus by moving the lens elements internally, so there are no IR filter interference problems, but they do cost more. Here's a typical set of spectra for IR LEDs. Not very large, but it gives a pretty good idea of the cutoffs. Google images for IR LED spectrum for more examples:

I'll just add my US$0.02 and echo the other inputs. IP cams are just as much about software and support quality as they are optics and video quality, and many would say software is more important. This is different from analog cams. If you have issues with poorly-supported cameras, you will spend many hours struggling with them, and there won't be much community support to help you. No-name or off-brand cameras will save you money up front, but they will cost far more in the long run. I wouldn't buy any camera that didn't have broad community support on the forums, as well as a vendor website with easy firmware downloads and accessible technical support, unless I was prepared to throw it in the junk box if things didn't work out.

It depends on the software. Re-encoding causes a big hit on CPU, so many/most systems dump the video straight to disk, though they may put it in a proprietary wrapper. Some NVRs can control the camera directly, especially if they're from the same manufacturer, while others just take what the camera is sending, and any changes need to be done on the camera. ONVIF is not very cross-compatible yet, so you'll want to be sure whatever you're looking at will support the cameras you have now.

Those are good points. When I first tested the Hik bullet against the Dahua bullet, the Hik's night images were much better, and it took me about a week to realize that the Dahua IR (which can't be disabled) was helping the Hik's night image quality a lot. I had to turn off the Dahua completely to get a real-world night image from the Hik.

I'd agree on the lux meter. I also have an Extech, and they're the best value in general, but I rarely use it for camera testing.

I'd agree that they're dust particles. I see them frequently on my Dahua and Hik cams, but not my older Vivotek and Messoa cams. I believe the reason is that the Dahua and Hik have stronger IR and more depth of field in the focus, so that the near particles are both more illuminated and more in focus, causing them to show up better. My Hiks show storms of particles after someone walks by at night, and it's very repeatable. I found some footage of raccoons that didn't trigger the motion detect by their own movement, but after they went by, there was a flurry of dust particles that triggered motion detect. I went to my 24x7 backup recorder and checked a few moments earlier, and there they were. This needs more data to know why some cams do it more than others, but that's my current theory.

If you want to learn some of the ins and outs of IP cams, it's not a bad idea to start with a camera with a varifocal lens. Also, a 3 axis dome and a bullet are good for learning, as there are differences in how they're mounted and deployed. Here's what I'd use for a learning setup: - A couple of different cams, like the 3 axis dome and bullet, maybe one vari-focal and one fixed, or whatever you're interested in - Some spare lenses if you get a fixed lens cam; lots to learn there! - A POE switch and cables - An inexpensive IR illuminator from Amazon - A motion detect white light - A PC or laptop - A variety of software to test out - Blue Iris demo version, Milestone Xprotect Go free version, whatever came with the cameras, and any other demos that sound interesting - Some targets that will give you reproducible results, like the ISO 12233 chart, the Siemens star, and anything else that might fill your needs. You'll want some areas with different illumination to test, depending on what your uses may be. A typical suburban street with streetlights, a dark back yard, whatever. Many cams these days don't have standard screw mounts. For the ones that do, I like a tall tripod for testing; it allows you to move the camera around easily and keeps it stable. For other cams, I use a ladder and a towel; the towel helps aim it and stabilize it, but anything that works is good. I've also mounted some on boards and hung them from hooks in the eaves. That should be enough to keep you busy for months!

You should be able to hear the filter click in and out if it's working. It's not a loud sound, and best bet is to try with a camera that's working, then compare to the suspect camera. You can either shine a light in the sensor, then block it to make it switch, or have someone switch modes from the web screen. I have a Vivotek that switches in one orientation, but not when it's upside down, and you can tell the difference by a solid click vs a mushy click.

Looks like your IR filter might be stuck in the out position. Sometimes a good thump or two will free it up, but once it starts doing this, it will probably keep doing it.

There's a thread here that rolls up a few methods for connecting the cams to your network as well as the NVR. I also don't have one, but these seem to work: viewtopic.php?f=19&t=35962&start=0

The bright center is because the IR spot size is smaller than the field of view for that lens/sensor combo. Nothing to be done about that except diffusing the IR, which spreads it out and gives less range. That takes experimenting with diffusing films or materials, which usually have to be between the LEDs and the glass to avoid getting horrible IR reflections. These cams are a pain to do this with, due to the way they come apart. The overall look is typical low-light Hik performance. You can improve it by turning up the noise reduction to 100% and not using WDR at night. I also turn down the contrast some, though that causes its own image quality issues. Increasing the maximum exposure time gives a better low-light image, but going below 1/30 sec causes motion blur. Low-light image is one of the weak spots on these cameras.

Those questions are hard to answer accurately, because M12 lens vendors have flexible standards. Generally, you can't trust any of those numbers to be very precise. Also, both of those lenses appear to be IR corrected, not IR blocking, so your colors will be off with them. The 1/2.7" 2.8mm lens will pretty definitely give a wider angle than the 1/3" 3.6mm. Scaling for the different sensor sizes makes it look like it would be about a 3.1mm equivalent on a 1/3" sensor, but this is a pretty rough guess. The 1/2.5" lens looks like it would scale to about 3.3mm equivalent. The only way to be sure is to buy and try!

If you're looking for generic networked IO, there's quite a variety out there, but it tends to be pricey. http://www.industrialnetworking.com/Category/Ethernet-IO

I've had mostly good luck with my Vivoteks, but the Dahua and Hik cams give better value these days. Hiks are better overall, IMO, but Dahua has better low light images. I've never tried ACTi, but they're only a little more than Hik and Dahua, and reportedly provide better support.

Depending on which stream you're recording, you can adjust your record time. Stream1, with MJPEG at 1080p and 30 fps, will fill up a hard drive really quickly. Each frame is compressed with JPEG, but there's no frame to frame compression like with h.264. Stream2, with a bit rate of 2Mbps, will generate 1GB of data per minute. If there's no bit rate setting for Stream1, you'll have to either look at the recorded files and calculate it, or install something that lets you read the bit rate for each cam. Blue Iris will show you the actual bit rate of each camera in real time (in kB/sec, not kb/sec), and you can install the demo version to see this. There's probably other software that will do it, but BI is what I use.

My Dahua HFW3300C can be set for MJPEG, and I viewed it on the browser as well as in an NVR, but I don't remember the connection details. It was a very ugly video stream - colors all screwy, lots of pixellization, essentially unusable. I haven't tried again recently.

If you get a tablet with HDMI out (or any video standard), you can use that. Likewise, some people use the little Android mini PCs like the UG802 to connect to the cams and display on a TV. I use a 10" tablet as a portable viewer around the house. Buellwinkle's got a review on using the UG802: http://www.networkcameracritic.com/?p=1049