string originalFileName;
    using (CameraCaptureDialog dlg = new CameraCaptureDialog()) {
        dlg.Mode = CameraCaptureMode.Still;
        dlg.StillQuality = CameraCaptureStillQuality.Low;
        //dlg.Resolution = new Size(800,600);
        dlg.Title = "Take the picture";
        DialogResult res;
        try {
            res = dlg.ShowDialog();
        }
        catch (Exception ex) {
            Trace.WriteLine(ex);
            return null;
        }

        if (res != DialogResult.OK)
            return null;
        this.Refresh();
        originalFileName = pictureFileName = dlg.FileName;
    }

后来编辑：
你们中的一些人也可能会发现这个链接很有用：
http://community.intermec.com/t5/General-Development-Developer/CN50-MS-Camera-Capture-Dialog-generates-error/m-p/12881#M4083