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In case when I have locked white balance and custom exposure, on black background when I introduce new object in view, both objects become brighter. How to turn off this feature or compensate for that change in a performant way? This is how I configure the session, note that Im setting a video format which supports at least 180 fps which is required for my needs. private func configureSession() { self.sessionQueue.async { [self] in //MARK: Init session guard let session = try? validSession() else { fatalError("Session is unexpectedly nil") } session.beginConfiguration() guard let device = AVCaptureDevice.default(AVCaptureDevice.DeviceType.builtInWideAngleCamera, for:AVMediaType.video, position: .back) else { fatalError("Video Device is unexpectedly nil") } guard let videoDeviceInput: AVCaptureDeviceInput = try? AVCaptureDeviceInput(device:device) else { fatalError("videoDeviceInput is unexpectedly nil") } guard session.canAddInput(videoDeviceInput) else { fatalError("videoDeviceInput could not be added") } session.addInput(videoDeviceInput) self.videoDeviceInput = videoDeviceInput self.videoDevice = device //MARK: Connect session IO let dataOutput = AVCaptureVideoDataOutput() dataOutput.setSampleBufferDelegate(self, queue: sampleBufferQueue) session.automaticallyConfiguresCaptureDeviceForWideColor = false guard session.canAddOutput(dataOutput) else { fatalError("Could not add video data output") } session.addOutput(dataOutput) dataOutput.alwaysDiscardsLateVideoFrames = true dataOutput.videoSettings = [ String(kCVPixelBufferPixelFormatTypeKey): pixelFormat.rawValue ] if let captureConnection = dataOutput.connection(with: .video) { captureConnection.preferredVideoStabilizationMode = .off captureConnection.isEnabled = true } else { fatalError("No Capture Connection for the session") } //MARK: Configure AVCaptureDevice do { try device.lockForConfiguration() } catch { fatalError(error.localizedDescription) } if let format = format(fps: fps, minWidth: minWidth, format: pixelFormat) { // 180FPS, YUV layout device.activeFormat = format device.activeVideoMinFrameDuration = CMTime(value: 1, timescale: CMTimeScale(fps)) device.activeVideoMaxFrameDuration = CMTime(value: 1, timescale: CMTimeScale(fps)) } else { fatalError("Compatible format not found") } device.activeColorSpace = .sRGB device.isGlobalToneMappingEnabled = false device.automaticallyAdjustsVideoHDREnabled = false device.automaticallyAdjustsFaceDrivenAutoExposureEnabled = false device.isFaceDrivenAutoExposureEnabled = false device.setFocusModeLocked(lensPosition: 0.4) device.isSubjectAreaChangeMonitoringEnabled = false device.exposureMode = AVCaptureDevice.ExposureMode.custom let exp = CMTime(value: Int64(40), timescale: 100_000) let isoValue = min(max(40, device.activeFormat.minISO), device.activeFormat.maxISO) device.setExposureModeCustom(duration: exp, iso: isoValue) { t in } device.setWhiteBalanceModeLocked(with: AVCaptureDevice.WhiteBalanceGains(redGain: 1.0, greenGain: 1.0, blueGain: 1.0)) { (timestamp:CMTime) -> Void in } device.unlockForConfiguration() session.commitConfiguration() onAVSessionReady() } } This post (https://stackoverflow.com/questions/34511431/ios-avfoundation-different-photo-brightness-with-the-same-manual-exposure-set) suggests that the effect can be mitigated by settings camera exposure to .locked right after setting device.setExposureModeCustom(). This works properly only if used with async api and still does not influence the effect. Async approach: private func onAVSessionReady() { guard let device = device() else { fatalError("Device is unexpectedly nil") } guard let sesh = try? validSession() else { fatalError("Device is unexpectedly nil") } MCamSession.shared.activeFormat = device.activeFormat MCamSession.shared.currentDevice = device self.observer = SPSDeviceKVO(device: device, session: sesh) self.start() Task { await lockCamera(device) } } private func lockCamera(_ device: AVCaptureDevice) async { do { try device.lockForConfiguration() } catch { fatalError(error.localizedDescription) } _ = await device.setFocusModeLocked(lensPosition: 0.4) let exp = CMTime(value: Int64(40), timescale: 100_000) let isoValue = min(max(40, device.activeFormat.minISO), device.activeFormat.maxISO) _ = await device.setExposureModeCustom(duration: exp, iso: isoValue) _ = await device.setWhiteBalanceModeLocked(with: AVCaptureDevice.WhiteBalanceGains(redGain: 1.0, greenGain: 1.0, blueGain: 1.0)) device.exposureMode = AVCaptureDevice.ExposureMode.locked device.unlockForConfiguration() } private func configureSession() { // same session init as before ... onAVSessionReady() }