Strange shadow in amater setup videosurvelence

[Tomycrosound]

I have a HUHI7204K1 and 2 hikvision analog cameras. Have also some old bad camera. I bought another one, hik 5mp.. I had to call an installer to replace it because it is 7m high. He just screwed it in and left. I have a horizontal shadow in the upper part of the screen, if we watch the picture on a 55 TV, about 15cm high. During the day (through 10am) the thickness is the same but it has dropped 4-5cm lower. One cable that goes from thickening to thickening on the cameras has 3 wires, a single open and a red and blue thin wire. I also have a thin shadow on the left along the edge, 2cm thick if we watch on TV. All objects have a shadow, especially those in motion. I tested a different power supply for the camera. Shortened the cable. Changed the channel. Reset. What else can I do since I don't have access to the camera and the last 1.5m of cable? The cable is up to 10m in total length. max. Two other similar cameras don't have these problems. I noticed that their cable is shorter. I tested camera before montage on 20cm short improvised wire - no error.

 

[TonyR]

Can you post images of the issues?

What spec cable is being used? Coax video cable with a separate 12VDC power cable or a siamese (twin) cable with video and power?

Any CAT-5 cable with baluns (BALanced/UNbalanced cable Ethernet to BNC adapters) anywhere?

 

[Tomycrosound]

Can you post images of the issues?

What spec cable is being used? Coax video cable with a separate 12VDC power cable or a siamese (twin) cable with video and power?

Any CAT-5 cable with baluns (BALanced/UNbalanced cable Ethernet to BNC adapters) anywhere?

hello! I sent pvt.
The cable is one with 3 wires - uninsulated ground, one red and one blue wire. There is a plastic thickening (factory) on both ends from which two cables come out - BNC and power. The cable is 10m long in total, I cut 8 and put cat5 (or larger, cat cable with each pair separately wrapped) and connected it like that. No change. I replaced the balun to the DVR with the same one, no change. I can't get to the camera and this side of balun. Maybe a ground isolator would fix the double shadowing image, but not the shadow at the top of the screen. I don't know if it has to do with the sun or the time of the day, but it went down a bit during the day yestarday and now this morning it pulled higher again.

 

[TonyR]

Maybe a ground isolator would fix the double shadowing image, but not the shadow at the top of the screen.

It may but if the horizontal shadow is not animated (like old raster-scan TV interferance lines) it may not, but you won't know until you try.

It's also possible the camera's sensor has issues.

 

[Tomycrosound]

Right now, as I'm writing this, I'm looking at the picture after temporarily moving the DVR 2m away from the camera and messing with the wires. There is NO SHADOW on the top of the screen.

 

[Tomycrosound]

98% solved.
I've already tried with a cat (some number) cable and there was no progress.. GPT persuaded me to connect, for example, blue - video, blue-white ground, red video, red-white ground and those two ground wires together with a braided connection. And there is no shadow on top! There is a little mabe shadowing on object, but minimal. I find some ground isolator..

 

[TonyR]

98% solved.
I've already tried with a cat (some number) cable and there was no progress.. GPT persuaded me to connect, for example, blue - video, blue-white ground, red video, red-white ground and those two ground wires together with a braided connection. And there is no shadow on top! There is a little mabe shadowing on object, but minimal. I find some ground isolator..

If the consductors in that video cable are not properly overall shielded and/or have minimal twist (turns per foot) then crosstalk or adjacent interference, especially from nearby conductors connected to AC mains, is likely.

The ground loop isolator cannot hurt.