New Post: Convert tiff from RGB to CMYK

I am trying to convert an image from RGB to CMYK. No matter what I do, I cannot save the image as a decent CMYK format. It either saves as pixelated CMYK, or as a very nice RGB. But I need it to go to a printer. It must be high quality CMYK.

I've tried literally 100s of combinations of code. Here is where I am right now, but nothing I have tried works.

        string oldFile = "c:\\Temp\\agent-j-peck1Before.tif";
        string newFile = "c:\\Temp\\agent-j-peck1After.tif";
        if (File.Exists(newFile))
            File.Delete(newFile);
            MagickImage img = new MagickImage(oldFile);
            img.ColorSpace = ColorSpace.CMYK;
            img.CompressionMethod = CompressionMethod.LZW;
            img.Write(newFile);

You can download the image here to see the original. http://kitt.us/agent-j-peck1Before.tif

Note, when it does save it as CMYK, the quality drops to a fraction of the original.

Any help appreciated. I really need to have this done by Monday. I have been struggling with this for days.