在C＃中提高图像打印质量

Question

        panel1.BorderStyle = BorderStyle.None;
        Bitmap bitmap = new Bitmap(panel1.Width, panel1.Height);    // 226 Width , 147 Height
        panel1.DrawToBitmap(bitmap, panel1.ClientRectangle);
        pictureBox19.Image = bitmap;


e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
e.Graphics.InterpolationMode = stem.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
e.Graphics.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
e.Graphics.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceOver;
e.Graphics.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
e.Graphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAlias;

e.Graphics.DrawImage(pictureBox19.Image, 390, 120);

我对图像打印质量不满意。

用C＃改善图像打印质量的其他方法？