The 898x988 dimensions are the size with the DPI applied. If you want to get a larger image you should use the MagickReadSettings class and specify the Density.
MagickReadSettings settings = new MagickReadSettings(); settings.Density = new MagickGeometry(300, 300); // You can change this to get a better image.using (MagickImage image = new MagickImage("test.eps", settings)) { images.Write("test.png"); }