After a brief absence from home, I had a Zoom meeting, so I turned on my webcam and, much to my surprise, everything looked shifted far towards the red! I didn’t find anything in my OBS Studio settings nor in Zoom, but I was late for the meeting, so I had to switch back to my crappy internal webcam until I could sit down to figure out just what happened.

Just What Happened

I used guvcview to look at the settings of the camera. Fortunately, I have another camera, so I could do some basic A/B testing to isolate the problem. The other camera looked fine. The difference lay in a single setting: Saturation. On the “faulty” camera, it was set to 100; on the “working” camera, it was set to 50.

I don’t know how that setting was changed. The problem is solved!

A Neat Feature

The utility guvcview has the feature to save a profile to a plain text file, so I could save the settings on both cameras, then compare them with meld. Both cameras have the same settings now, so presumably they behave the same now. Great! I can even put these profiles into a version control repository as a baseline for the next time my camera does something strange.

Details

The cameras involved are Anker PowerConf C200 cameras and I experienced this problem on Pop!_OS 24.04. I also found a project that threatens to have CLI tools for PowerConf cameras: https://github.com/erans/anker-powerconf-c200-linux-tools. This project bears examining, but I haven’t done that yet.