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    Job site IP camera

    I notice the photo in the DS-2CD2335-I link you have has the "Hikvision" logo intentionally blurred out. I'm not sure if they mean they're selling an unbranded version, or something else but I suspect they are not showing a photo of the actual product they sell. Which makes me wonder what they...
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    ALPR: anyone have a 100mm lens they like?

    I put the previously shown test plate in the trunk of my car, left the lid up and drove down the street. This image is a 1:1 crop with Dahua 4MP and the Canon EF 100/2 lens, at a distance between 250 and 300 feet. You can see by the fuzziness of the taillights how far apart the 850nm and...
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    ALPR: anyone have a 100mm lens they like?

    Yes, I also had a Canon EF to CS mount adaptor handy. they are around $15 on ebay. Canon EOS EF EFs lens to C Mount Film Movie Bolex Video Camera CCTV Adapter Ring | eBay It's a pretty righteous lens for the little box camera, but the mount has held up to the weight, so far. If I didn't...
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    ALPR: anyone have a 100mm lens they like?

    UPDATE! I just tried a Canon EF 100mm f/2 lens I happened to have on the shelf, obviously big & heavy but holy cow it's so much better, there is no comparison. No need to stop it down; even wide open the image is crisp. From 250 feet I can read a dealership phone number printed along the edge...
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    ALPR: anyone have a 100mm lens they like?

    Thanks for the tip @nayr about WDR. I enabled that and a setting of 25 makes the picture low-contrast, but ALPR seems to like it just fine. Here's a car somewhere around 200 or 250 ft. Since then I've backed off the WDR settings to 18.
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    ALPR: anyone have a 100mm lens they like?

    Right now I use a shutter speed of 1/500 during the day and 1/120 at night. The one good thing about the view under the trees is it's almost exactly along the road. Also that's a T junction just before the house at the end, so there's a limit to how fast cars will go. Result is hardly any motion...
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    ALPR: anyone have a 100mm lens they like?

    Absolutely a good PTZ would be easier. First thing I tried was a Sunba mini-PTZ with lens to 94mm and the hardware was OK but firmware very poor. No manual exposure! night images totally overexposed. Also cannot view horizon, about five or ten degrees short. Awkward to mount the thing tilted to...
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    ALPR: anyone have a 100mm lens they like?

    So far I am happier with this lens at night, than during the day, but I'll see if I can focus it better this weekend. Here are a few shots using the 5-100mm Speco zoom lens at the long end, on the Dahua 4MP box camera. The night shot is a 1:1 crop where I am holding the plate at a distance of...
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    ALPR: anyone have a 100mm lens they like?

    Sure, I will post some. I want to actually set up a plate at a known distance. With such a long lens looking along the road, as a random car drives it is hard to tell exactly how far away it is. One thing I can say is you definitely need to refocus morning & evening, because the 850nm IR and...
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    ALPR: anyone have a 100mm lens they like?

    In case anyone else needs a long lens: I finally got one, and can confirm this particular model works pretty well on the 4 MP Dahua box camera for reading plates at 250-300 feet. SPECO TECHNOLOGIES VF5100DC 5-100mm Auto Iris Lens CS Mount Amazon.com : SPECO TECHNOLOGIES VF5100DC 5-100mm Auto...
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    door checkers caught

    From the title I assumed you meant just "caught on video", but I was amazed to see caught by police! Impressive. Actually apprehending these guys just never happens in my neighborhood. I guess, if I was willing to spend every night from 2-4 am watching the cameras, maybe they could be. Or if...
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    Dedicated License Plate Cam project

    Nayr speaks the truth... 250-300 feet is a real challenge. Right now, using the 4MP Dahua with 40 mm lens I actually get legible-by-eye plates to about 250 ft at night. Not quite good enough image quality for reliable ALPR at this time. For example, below image is a 2x digital zoom of a car...
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    Sunba HZ507-20XB Mini Dome PTZ Camera

    Thanks for the reply lulu5, I tried every setting, with no effect. Sunba tech support was very quick, but ineffective- they sent me a new firmware, and suggested some settings. I tried them all, but without result. Apparently this camera does not have a manual exposure mode at night. During the...
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    ALPR: anyone have a 100mm lens they like?

    Thanks- yes, I do have a Canon EF - CS lens mount adaptor from ebay. I tested a Sigma 70mm macro and it works, I was just hoping to avoid using a big heavy expensive DSLR lens, and I also wanted a lens with auto-iris the IP cam could control. But maybe the DSLR lens is my only real option at...
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    Dedicated License Plate Cam project

    If I didn't want LPR, I'd probably keep the camera. The 20x zoom is decent and it's less expensive than similar alternatives. Apart from fixed gain-up at nighttime, the other annoyance is it will not look directly horizontal; only about 5 or 10 degrees short of it, and if you try to cheat and...
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    Sunba HZ507-20XB Mini Dome PTZ Camera

    Has anyone been able to get the Sunba 507-20XB to UNDEREXPOSE at night (turn gain way down)? I have to do that to see details on cars past the headlight glare. None of the camera's setup exposure controls in the IE plugin seem to have any effect on the image at night, although they do function...
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    Dedicated License Plate Cam project

    @blake I got the non-POE version from that Amazon link, it comes with a 12V 2A adaptor. I may have spoken too soon- during the day it worked fine. At night, the image is too bright (gain up full) so all plates are completely washed out. There are several exposure settings in the MSIE browser...
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    Dedicated License Plate Cam project

    I got the same 4MP Dahua box camera nayr has for ALPR (see his signature) and it's fine so far as it goes, but in my particular situation I was unable to get a long enough lens (100mm or so) to work at 300 feet which is what I need. So today I took delivery of a Sunba 20x PTZ, and it does the...
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    Dedicated License Plate Cam project

    Yes, there are retroreflective spray paints, and plate covers sold for the express purpose of blocking traffic cameras. Search for "license plate blocker" to see examples
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    Dedicated License Plate Cam project

    With the 4500mW "IR Cannon" recommended by nayr I'm getting good images... except when this kind of thing comes along. Coating worn off from too much hand detailing at the car wash, I assume, but you have to wonder if people don't do it intentionally.
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    ALPR: anyone have a 100mm lens they like?

    It is curious... I have now tried to order three different kinds of CS-mount 100mm lens from three separate suppliers (ebay, Amazon, and B&H Photo in New York). In each case, after several days, the vendor replied that the supposedly in-stock lens is either simply not available, or backordered...
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    Dahua Starlight Varifocal Turret (IPC-HDW5231R-Z)

    If you're using 850nm IR illumination (or 940nm for that matter) it wouldn't matter much. The Bayer-pattern color filters (dye spots) on the chip are all nearly transparent at those wavelengths, so a true monochome sensor without the color filters would not improve sensitivity. If you want best...
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    Dedicated License Plate Cam project

    I recently found out from Matt (author of OpenALPR) that it has trouble with plate frames that touch or partly cover the bottom of the letters on the plate. Google Groups He said there is an experimental software feature to address the problem, but apparently it is not available in the free...
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    IR Cannon w/Adjustable Focus

    It took 32 days to get here, but arrive it did (this one). In case anyone is interested, there are three LEDs inside. They are in series, 1.18 A runs through each one, Vf = 1.8V each for total 5.4 V, so total power into LEDs is 1.18 * 5.4 = 6.4 watts. Almost the entire interior volume is one...
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    Looking for a LPR camera

    I'll be interested to find out the answer- all the LPR experience I've seen in this forum is by people using OpenALPR running on separate hardware from the camera. I believe in-camera recognition is significantly more expensive. Also, working at 60 mph requires a very nearly on-axis camera...
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    installation best practice

    Ah, you mean physical install details, not choice of cameras. For keeping cables in place, I like the little nail-in cable clips https://www.amazon.com/Your-Cable-Store-Ethernet-6mm/dp/B00481IPZY but I don't know if that's a "best practice". Strictly speaking, for any exposed outdoor runs I...
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    SUNBA - cheap PTZ with 20x zoom?

    As you say, your example image looks perfectly good for LPR, and even the model name is clear. I may just be asking too much of the lens to reach 300' because I'm not getting quite as solid an image as you show. Maybe OK by eye but ALPR struggles with it. At night, still enough light around...
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    SUNBA - cheap PTZ with 20x zoom?

    Yes, that's a good point about the depth of field. I played with the focus for a while, but couldn't quite get a usable image at distance. At this point I'm thinking about trying a good quality 5-100mm lens like Kowa LMVZ510A 1/3" Varifocal Auto-Iris Lens LMVZ510A B&H
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    SUNBA - cheap PTZ with 20x zoom?

    I do appreciate your viewpoint and I agree you can't specify a lens is good for "X megapixels". That said, in the past several years I've got a reasonable number, more than 20 different lenses (including M12 and C/CS mount) which I've put on various IP cameras and I have found the ones I like...
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    SUNBA - cheap PTZ with 20x zoom?

    For my long-distance LPR application I need a long zoom lens, like 100 mm. I have a Dahua 4MP box camera with a 60mm lens and I found it isn't quite good enough. All of the CS-mount lenses of ~100mm focal length I have found seem to be intended for old-school standard-def analog cameras, not...
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