Dahua CVI line across screen and IR glare?

GH75

Young grasshopper
Mar 4, 2016
58
10
I know this is an IP forum but can we post about CVI here?

Just installed 3 1080P CVI varifocal domes. All 3 have the line issue shown in the video. This one has the whiteout that looks like IR glare. The focus is the gazebo, so I could probably zoom in some, not sure if that will fix it.

Any suggestions?

 
CVI amateur here, but both I think apply to any camera type. The glare seems to be a more common issue with dome cameras due to the reflection off the glass/plastic covering. Perhaps there's something shiny at 5 o'clock just below the camera you can move or cover?

The line I believe is from a power source, possibly your cabling too close to or laying across 110V power cable? I've also seen explanations about that being related to the power supply itself...I had horizontal scrolling similar about 4 years after install on 2 cameras and both times the Cat5 had succumbed to the elements/critters where I had done a lousy job of running the cable.

Maybe try plugging the camera directly into your DVR to isolate the cabling as a source of the scrolling line...
 
looks like you buried some of the IR behind the mounting and its now ruined the night image.. a dome was a poor choice, you have to change the FOV until it goes away.

make sure you insulated your connections and you dont have a plug laying against some siding or anything like that.
 
Same camera from earlier in the day. At this point I am pretty sure there is no interference. The lines run from a pool house to some light poles. The pool house has no lights, and at this point the tennis court lights were not on. There is nothing electrical to cause interference that I can see.

This was an existing 14 camera analog system where we put in a tri-brid DVR and changed 3 cameras to analog. So I do not know where all the lines run.

There is nothing blocking the IR. The cameras are 12-13' off the ground on poles. No trees. These cameras do not have any internal housing to block IR. You just rotate the lens and put the dome on.

EDIT: After watching the day video, you think maybe the IR is bouncing off the fence?

Domes were the whole point of this project. The client did not want the bullets.

 
the plastic will start to fog up, you get UV reflections like this.. do they not make turret CVI cameras?

tho i guess a tennis court does seem somewhat appropriate with balls flying all over the place.. much better excuse than most so I'll relent.

its hard to say what the reflection is though, that curved plastic dome can catch light from all over the place.. zooming in probably wont help, think its best to play with the angles at night until it goes away.. then you can figure out what it was and if you have any options to work with it.

can you disable onboard IR and go w/external?

the line looks like a power issue, mebe bad ground.. is the NVR grounded or are you just using the 2 prong DC adapter and leaving the grounding screw floating?
 
Give each camera it's own power supply rather than using one common one. I have seen this occur often with CVI cameras. They don't like power supplies that use a common ground.
 
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I am going back out Tuesday.

The IR issue should not be an issue. I should be able to move the camera to the left off the fence, and ensure the foam around the lens is against the glass.

How can I duplicate this during the day? Put a box over the camera? cover the light sensor? This place is 1.5 hours/ 80 miles away. I do not want to go back twice, and I would rather not stay till 8PM....

I ordered dedicated power supplies, and ground loop isolators. Do the isolators go at the head end or camera?

I will post results.

With my former company we have literally put up 100's of these and never seen this issue.....

Thanks to everyone who chimed in
 
iirc there is a full solar eclipse for north america just under a year from now..

unless you got a box big enough to fit that tennis court in, how exactly are you going to be confident the reflections are gone? If its a 1.5h drive, you should probably just stay late.. FYI the sunsets at 6pm now
 
Give each camera it's own power supply rather than using one common one. I have seen this occur often with CVI cameras. They don't like power supplies that use a common ground.

Update

ding ding for vector.

The system was using a 16 or 18 way CCTV power distribution style. I installed the ground loop isolator and nothing. I removed the isolator, crossed my fingers (mind you I have a DVR, 3 cameras and labor invoice hinging on this) and installed the dedicated power supply. Problem solved on all 3 cameras.

The IR issue did not seem as bad when I went back but I reaimed off the fence and ensured the rubber around the lens was touching the glass.

All issues resolved last night and invoice sent off today !

BTW Nayr, we prefer domes because we do alot of multi family and people tend to tamper with bullets. Turrets may be less prone but still possible unless installed fairly high.

Thanks all