Had an issue where several cameras (5) seemed to be stuck in night Mode: i.e. The image was only showing in black & white.
Going to the CAmera GUI to select Day mode, just gave a Black Image.
Setting it to Auto Iris, was the same as being in Night Mode.
So no color image was available from the camera.
Resolution:
Turned out that the Lens Iris cable was not connected properly to the Camera Body and was not visible as the camera was in a housing.
After Firmly connecting the cable to the camera body, the Issue was resolved!
