Camera exposure/colour issue

[jarrah31]

Hi Michel,

I know this isn't related to your software but I hoped you may have some idea what the problem might be please? (feel free to tell me to look elsewhere) :)

As seen in the picture below, my camera feed has a red tint when compared to the same camera using RPi Web Cam software.

Rpi Web Cam:

V4L2:

All exposure and auto-white balance seem fine too:

$ v4l2-ctl -l

User Controls

                     brightness 0x00980900 (int)    : min=0 max=100 step=1 default=50 value=50 flags=slider
                       contrast 0x00980901 (int)    : min=-100 max=100 step=1 default=0 value=0 flags=slider
                     saturation 0x00980902 (int)    : min=-100 max=100 step=1 default=0 value=0 flags=slider
                    red_balance 0x0098090e (int)    : min=1 max=7999 step=1 default=1000 value=1000 flags=slider
                   blue_balance 0x0098090f (int)    : min=1 max=7999 step=1 default=1000 value=1000 flags=slider
                horizontal_flip 0x00980914 (bool)   : default=0 value=0
                  vertical_flip 0x00980915 (bool)   : default=0 value=0
           power_line_frequency 0x00980918 (menu)   : min=0 max=3 default=1 value=1
                      sharpness 0x0098091b (int)    : min=-100 max=100 step=1 default=0 value=0 flags=slider
                  color_effects 0x0098091f (menu)   : min=0 max=15 default=0 value=0
                         rotate 0x00980922 (int)    : min=0 max=360 step=90 default=0 value=180 flags=modify-layout
             color_effects_cbcr 0x0098092a (int)    : min=0 max=65535 step=1 default=32896 value=32896

Codec Controls

             video_bitrate_mode 0x009909ce (menu)   : min=0 max=1 default=0 value=0 flags=update
                  video_bitrate 0x009909cf (int)    : min=25000 max=25000000 step=25000 default=10000000 value=10000000
         repeat_sequence_header 0x009909e2 (bool)   : default=0 value=0
            h264_i_frame_period 0x00990a66 (int)    : min=0 max=2147483647 step=1 default=60 value=60
                     h264_level 0x00990a67 (menu)   : min=0 max=11 default=11 value=11
                   h264_profile 0x00990a6b (menu)   : min=0 max=4 default=4 value=4

Camera Controls

                  auto_exposure 0x009a0901 (menu)   : min=0 max=3 default=0 value=0
         exposure_time_absolute 0x009a0902 (int)    : min=1 max=10000 step=1 default=1000 value=1000
     exposure_dynamic_framerate 0x009a0903 (bool)   : default=0 value=0
             auto_exposure_bias 0x009a0913 (intmenu): min=0 max=24 default=12 value=12
      white_balance_auto_preset 0x009a0914 (menu)   : min=0 max=10 default=1 value=1
            image_stabilization 0x009a0916 (bool)   : default=0 value=0
                iso_sensitivity 0x009a0917 (intmenu): min=0 max=4 default=0 value=0
           iso_sensitivity_auto 0x009a0918 (menu)   : min=0 max=1 default=1 value=1
         exposure_metering_mode 0x009a0919 (menu)   : min=0 max=2 default=0 value=0
                     scene_mode 0x009a091a (menu)   : min=0 max=13 default=0 value=0

JPEG Compression Controls

            compression_quality 0x009d0903 (int)    : min=1 max=100 step=1 default=30 value=30

Thanks!

[jarrah31]

Hmm, so changing white_balance_auto_preset to any number makes no difference, but as soon as I set it to 0 (manual), it corrects the colour. Changing back to 1 (auto) does nothing either. In fact, the only way to go back to the red tint is restarting v4l2rtspserver, then I have to set to manual and then auto. Strange!

I have this set up on another outdoor Pi Camera and that works fine, with none of the issues I'm seeing here. Happy to close this unless you have any ideas why it might be happening?

[lost-carrier]

Hmm... thanks for that post... same here!

...can work around it, but something's fishy with this...