private void button2_Click(object sender, EventArgs e)
{
const string wiaFormatJPEG = "{B96B3CAE-0728-11D3-9D7B-0000F81EF32E}";
CommonDialogClass wiaDiag = new CommonDialogClass();
WIA.ImageFile wiaImage = null;
wiaImage = wiaDiag.ShowAcquireImage(
WiaDeviceType.UnspecifiedDeviceType,
WiaImageIntent.GrayscaleIntent,
WiaImageBias.MaximizeQuality,
wiaFormatJPEG, true, true, false);
WIA.Vector vector = wiaImage.FileData;
Image i = Image.FromStream(new MemoryStream((byte[])vector.get_BinaryData()));
i.Save(@"D:\prueba1.jpeg");
}
Final solution works perfectly.