Which 4k/8mp color night vision cameras???

I dont know much at all about the cameras, but I do know audio/video.
And for some reason, one thing I rarely hear discussed is what display is being used in these comparisons.
The greatest 4k camera in the world will look good, amd you can notice differences in quality per camera on a 1080p display, but still isnt what it should be.
 
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triumph202 said:
Hey, if you're still watching this thread, I have a question about what you said about the f1.0 lens on your Colorvu and not being able to focus on anything closer than 3.6m. I had a Dahua 4KX 2.8mm that wouldn't get a reasonable focus on anything closer than 10ft. In the image you posted below, I see the driveway bricks that are closest to the camera on the left appear blurry. Is this from the lighting, or are they actually out of focus? If someone / something was within 4-8 feet of the camera, would they be blurry?

Hikvision 4mm 8MP G2 Colorvu
View attachment 134001

I have blurred out the car plate number on my car apart from the first letter. The 5231 was zoomed in a bit to compensate for it having less pixels, but when there isn't enough light the zoom is useless.

The f1.0 lenses on the 8MP Colourvu can present issues with focus for close up subjects. The minimum focus distance is greater than 3.6m for the 4mm versions I have.
Click to expand...
 
^Keep in mind if you read this whole thread, he had his parameters all jacked up so it wasn't much of a useful comparison...
 
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IAmWatchingYou! said:
Hey, if you're still watching this thread, I have a question about what you said about the f1.0 lens on your Colorvu and not being able to focus on anything closer than 3.6m. I had a Dahua 4KX 2.8mm that wouldn't get a reasonable focus on anything closer than 10ft. In the image you posted below, I see the driveway bricks that are closest to the camera on the left appear blurry. Is this from the lighting, or are they actually out of focus? If someone / something was within 4-8 feet of the camera, would they be blurry?
Click to expand...

Ignore the useless responses posted on here by someone who has never seen the lighting conditions at my place.

That camera came badly focussed from new, with the LHS being worse. I adjusted it (as best I could) but the LHS is still out of focus compared to the rest of the picture. You'd need to check the minimum focus distance of that model Dahua in their published specs. Low light cameras, which use lenses with large apertures to let in more light (like f1.0), will suffer from a narrower "in focus" zone than other cameras which use smaller aperture openings (like f1.6 and higher.) You should be able to refocus the lens if you pull it apart and adjust it so the closer range is focussed, but the long distance focus will then be out.

Someone within the 3.6m minimum focus distance of my camera will begin to appear out of focus- worse the closer they get to the camera.
 
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Thanks for the reply @triumph202 and sharing that about the info about lens aperture. I spent some time reading and catching up on basic photography, and reading how a large aperture reduces the "depth of field" (in-focus range / zone). The Dahua camera says its "Max Aperture" is F1.0. I'm not sure why they threw the word "Max" in there, but now I understand that F1.0 is a huge aperture, and probably explains why anything closer than 10 feet is blurry with the Dahua camera. That must mean Dahua had to decide between making near objects in-focus, or far objects in-focus, and decided on far. However, that makes the camera useless when mounted in areas where some of your subject are going to be close to the camera. I would love to keep the camera in hopes of being able to adjust the focus, but it sounds like if I were to adjust the focus it would be a bit of a gamble as to what the distance of the long range focus I would lose would be. (I have about 25' in front - very similar to your situation, and about 60' in back I'd like to but cameras to cover. In front there are definitely spots that without burning $$ on a pile of cameras, someone could sneak up on the left or right side and be out of focus on one of these F1.0 cameras. It's also not comforting to look at a camera and see part of the image and people walking by be blurry.

Would you choose a 4MP with a 1/1.8mm F1.6 or higher lens if you were to go back and decide again? Or, does the low light capability outweigh the focus issues?

I was reading about adjusting the focus in these fixed focus cameras after your reply, and read where @tigerwillow1 had a similar issue to you where a portion of the view was out of focus (last post on the bottom):

Anyone tried adjusting focus on Dahua fixed-lens turrets?

I'm wondering if focus can be improved on my cam, this seems sub-standard. I see the same effect at night on reflective license plates, definite "ghosting." It's a Dahua fixed-lens turret/eyeball. I would consider disassembling it if I could get a better result.
ipcamtalk.com ipcamtalk.com
It sounds like that's a manufacturing defect with the camera / how the lens was mounted? In my case it's everything that's within 10' of the camera.


One last thing - do you still like the human / vehicle detection in the Hikvision? How is it with false alarms and have you spent any time analyzing the video for misses?
What I want to do is have one IVS rule that does push alerts and records for humans entering my property, and a second IVS rule that just records for humans and vehicles on the sidewalk and in the street. Is that do-able with your DS-2CD2387G2-LU?
 
what i've learned about all this worrying, it gets solved when the actual incidents happen, and you discover where your cam game is weak, all this fiddle fuckin around needs real world incidents or at least go put on a hoodie and a kn-95 mask and see how your perp id is then,...thats when you hope you can get a plate or a car description...
 
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and he parked up the street and avoided lpr
 
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IAmWatchingYou! said:
Would you choose a 4MP with a 1/1.8mm F1.6 or higher lens if you were to go back and decide again? Or, does the low light capability outweigh the focus issues?
Click to expand...
It's an issue with that is worse with that camera. I was looking at the 4MP Colorvu and the minimum focus distance was worse (IIRC) for a given FOV. (Could be wrong there.) The low light capability was very high on my priority list, plus more pixels to improve the chances of getting more detail further away. My whole front yard is wide open - no side fences even between neighbours so I need a wider FOV. And there's only the one street light.
IAmWatchingYou! said:
One last thing - do you still like the human / vehicle detection in the Hikvision? How is it with false alarms and have you spent any time analyzing the video for misses?
Click to expand...
That's by far been the best feature for minimising false alerts. You can adjust sensitivity etc. I used to get annoying false alerts from moths/ insects, leaves blowing around, branches causing shadows etc. I haven't found it to miss any vehicles/ people in the detection zone.
IAmWatchingYou! said:
What I want to do is have one IVS rule that does push alerts and records for humans entering my property, and a second IVS rule that just records for humans and vehicles on the sidewalk and in the street. Is that do-able with your DS-2CD2387G2-LU?
Click to expand...
I'm not sure about the alert side of things, but I use an NVR and can just play back the Smart Alerts generated from the camera which gives me humans and vehicles.
 
sebastiantombs said:
Remember, too, that sensor sizes are fractions and therefor inverse of what they may seem to be.

Disclaimer - These sizes are what the manufacturers advertise and may, or may not, be the true size of the sensor in the camera.
1/3" = .333" Great for 720P
1/2.8" = .357" (think a .38 caliber bullet) Great for 2MP
1/1.8" = .555" (bigger than a .50 caliber bullet or ball) Great for 4MP
1/1.2" = .833" (bigger than a 20mm chain gun round) Great for 8MP
Click to expand...

Thank you
According to your advice, these are the best models that can be purchased from Hikvision, right?
For 2MP
2CD2027G2-L
or
2CD2T27G2-L
--
For 4MP
2CD2047G2-L
or
2CD2T47G2-L
--
For 8MP
2CD2087G2-L
or
2CD2T87G2-L

And Does your advice include cameras that are not equipped with Colors Vu and contain only IR?
 
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