void SetWhiteBalanceGains (AVCaptureWhiteBalanceGains gains)
{
NSError error = null;
if (VideoDevice.LockForConfiguration (out error)) {
AVCaptureWhiteBalanceGains newGains = NormalizeGains (gains); // Conversion can yield out-of-bound values, cap to limits
VideoDevice.SetWhiteBalanceModeLockedWithDeviceWhiteBalanceGains (newGains, null);
VideoDevice.UnlockForConfiguration ();
} else {
Console.WriteLine ($"Could not lock device for configuration: {error}");
}
}