I would test each one in day night and with different cables and connectors so that you can narrow down what the exact problem is.
My security camera is fuzzy at night.
The light coming from infrared leds in the camera gets reflected back to the camera which causes noise and blur in the night view.
If it it cloudy.
Best poe outdoor security camera system rlk8 410b4 the poe security system reolink rlk8 410b4 allows you to record videos via 4 poe ip rlc 410 cameras and store them to an 8 channel nvr.
Check the security ip camera lens for dirt dust spiderwebs etc.
Security cameras can be blurry because the lens might be out of focus the lens may be dirty water droplets on the glass dome are causing the light to reflect back into the lens the cameras image sensor is defective or the camera might be a low resolution camera which will look blurry compared to other high definition cameras.
When condensation forms on a security camera it can blur lenses and compromise image quality.
Condensation occurs on the warm side of the glass.
Part of the problem sounds like it could be a power issues with the cameras not getting enough power.
Do not use harsh cleaners or aerosol cleaners that may harm the lens.
Also all data transmission of this system is done via ethernet cables simple and stable.
That means taking all the cameras off line and working on them one at at time.
Security cameras night vision can get blurry due to reflective objects in the camera field of view.
To solve the problem just start simply by removing the camera dome at night time if possible to observe if the glass is causing the blurry or foggy effect.
If the security camera feed is fuzzy and not clear then another reason behind this could be an extra long extension cable run.
Long extension cables make it difficult for the signal to pass properly sometimes.
The extension cable run may be too long.
The infrared cut removal.
Condensation is because of 2 factors humidity and temperature difference between the air and the camera.
Another common issue with security camera blurry at night is related to the infrared light during the day there s a lot of light coming from the sun and some security camera uses a filter to block the infrared light so the camera image sensor doesn t get excessive and unnecessary light.
For example mirrors windows and objects made of glass.
When dealing with the security camera blurry at night problem the solution can be as easy as clean the camera dome glass or more complex as a bad camera or lens.