static IEnumerable<NSString> AllSessionPresets ()
{
yield return AVCaptureSession.PresetPhoto;
yield return AVCaptureSession.PresetLow;
yield return AVCaptureSession.PresetMedium;
yield return AVCaptureSession.PresetHigh;
yield return AVCaptureSession.Preset352x288;
yield return AVCaptureSession.Preset640x480;
yield return AVCaptureSession.Preset1280x720;
yield return AVCaptureSession.PresetiFrame960x540;
yield return AVCaptureSession.PresetiFrame1280x720;
yield return AVCaptureSession.Preset1920x1080;
yield return AVCaptureSession.Preset3840x2160;
}
}