Hi everyone, I’m stuck with a camera exposure issue and hoping someone can point me in the right direction. I’m using a UC-733 Rev.C1 UVC adapter with a Raspberry Pi HQ camera (IMX477), connected to a PC running Ubuntu 20.04. It shows up as /dev/video2 and I followed the instructions on docs.arducam.com.
The problem: the camera doesn’t respond at all when I change the exposure value. I’ve set auto exposure to manual, and I’ve tried changing exposure through both v4l2 and OpenCV. In both cases the value does change when I run v4l2-ctl -d /dev/video2 --all - the new exposure value is reported there - but the actual image doesn’t change at all. Attached a screenshot of the output I’m seeing.
Thanks for the detailed report. Can you try adjusting the exposure through VLC on Ubuntu? It exposes the v4l2 controls directly and is a good cross-check against v4l2-ctl/OpenCV.
Install VLC, open a terminal and run vlc, then press Ctrl + E to open the v4l2 control menu. Set the exposure value from there and see if the image responds.
Tried that as well. Installed VLC, opened it, pressed Ctrl + E, and changed the exposure value in the v4l2 control menu. The value sticks in the menu (and still shows the new value in v4l2-ctl), but the picture is still completely identical. No change in brightness or exposure at all.
Understood, thanks for testing. Could you share the exact product link for the adapter board you’re using? I’d like to reproduce this on our side with the same board to see what’s going on.
Thanks. We reproduced the behavior with that adapter - the exposure value changing but not affecting the image is down to the firmware on the board. I’ve sent you a new firmware package and a guide video through private message. Please check your messages, re-flash the firmware onto the adapter following the video, and then test the exposure change again.
Just re-flashed the firmware you sent and followed the guide video. Exposure changes now actually affect the image as expected. Problem solved, thanks for the help!