Print billede

Jeg skal printe et billede(et bitmap). Jeg har billedet i en instans af en picturebox. Derefter har jeg koden der er vedhaeftet i enden af dette. Problemet er at naar jeg skriver ud til papiret, saa kommer hele billedet ikke med. Den magler ca. 1/15 af billedet, hvilket jo ikke er optimalt. Hvad goer jeg forkert?



private void cmdPrint_Click(object sender, System.EventArgs e)
        {
            System.Drawing.Printing.PrintDocument document = new System.Drawing.Printing.PrintDocument();
            document.PrintPage += new System.Drawing.Printing.PrintPageEventHandler(this.PrintDocumentOnPrintPage );

            //having serious problems with this... irritating...
            document.DefaultPageSettings.Color = false;
            //document.DefaultPageSettings.Landscape = this.viewer1.Image.Width > this.viewer1.Image.Height;
/*            document.DefaultPageSettings.Margins.Left = 1;
            document.DefaultPageSettings.Margins.Right = 1;
            document.DefaultPageSettings.Margins.Top = 1;
            document.DefaultPageSettings.Margins.Bottom = 1;
*/
            this.printDialog1.Document = document;

            if(this.printDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK)
                document.Print();
        }

        private void PrintDocumentOnPrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs ppea )
        {
            Graphics grfx = ppea.Graphics;

            System.Diagnostics.Debug.WriteLine(ppea.PageSettings.PaperSize);
            System.Diagnostics.Debug.WriteLine(ppea.PageSettings.Bounds);
            System.Diagnostics.Debug.WriteLine(ppea.MarginBounds);
            System.Diagnostics.Debug.WriteLine(ppea.PageBounds);

            // I am having problems writing out complete picture, so that is why I add 1/20 in the end
            double scaleWidth = (double)ppea.MarginBounds.Width / (this.viewer1.Image.Width /* + this.viewer1.Image.Width / 20*/);
            double scaleHeight = (double)ppea.MarginBounds.Height / (this.viewer1.Image.Height /* + this.viewer1.Image.Height / 20*/ );
            double scale = scaleWidth < scaleHeight ? scaleWidth : scaleHeight;

            if(scale >= 1.0)
            {
                //print normal size
                grfx.DrawImage(this.viewer1.Image, 0, 0);
            }
            else
            {
                //ppea.Cancel = true;
                // print shrinked size
                grfx.DrawImage(
                    this.viewer1.Image,
                    new System.Drawing.Rectangle(ppea.MarginBounds.Left,ppea.MarginBounds.Top, (int)(this.viewer1.Image.Width * scale), (int)(this.viewer1.Image.Height * scale)),
                    new System.Drawing.Rectangle(0,0, this.viewer1.Image.Width, this.viewer1.Image.Height),
                    System.Drawing.GraphicsUnit.Pixel);
            }
            return;
        }

    }