Issues with JPEG Compressed TIFF Sizes - The quality parameter for TiffSettings and comparison with JPEG size

I am having several issues producing a JPEG compressed tif. My first issue is that no matter what quality I supply for the tiffSettings the file always comes out the same size. My second issue is that the file size for a JPEG compressed tif are a little more than double the comparable JPEG file. I would expect for the same compression level that the files would vary by a small amount to account for tiff tag bytes. Here are some samples that I adapted from the GraphicsMill sample code. I chose a quality of 100 to remove the first issue as a factor (or does it?).

Our scanner produces JPEG compressed tif files at a size consistent with my assumptions above. I'm not sure I have a way to verify the JPEG quality level of the scanner, but I doubt that it is less than 75 or so.

private static void WriteTiff()
{
    using (Bitmap bitmap = new Bitmap(@"C:\Users\Public\Pictures\Sample Pictures\Penguins.jpg"))
    {
        var tiffSettings = new TiffSettings()
        {
            Compression = CompressionType.Jpeg,
            Quality = 100
        };
 
        bitmap.Save(String.Format("C:/TestImages/file{0}.tif", DateTime.Now.ToString("MM-dd-yyyy-hh-mm-ss")), tiffSettings);
    }
}

private static void ReadAndWriteJpeg()
{
    using (Bitmap bitmap = new Bitmap(@"C:\Users\Public\Pictures\Sample Pictures\Penguins.jpg"))
    {
        var jpegSettings = new JpegSettings()
        {
            Quality = 100,
        };

        bitmap.Save(String.Format("C:/TestImages/file{0}.jpeg", DateTime.Now.ToString("MM-dd-yyyy-hh-mm-ss")), jpegSettings);
    }
}

The current version of Graphics Mill saves a JPEG image in the YUV format (the default behavior of the most software) and a TIFF image with JPEG compression in the RGB format. The RGB format improves the quality, but increases the output file size.

We have uniformed the behavior. The upcoming version of the SDK saves TIFF the same way as JPEG.

This feature will be included in the next release (> 8.0.37), which will be available in January 2016.