I'm using CS6 and can't figure out the following (I'm a newbie to illustrator). When I open a raster image, Illustrator always opens it at a smaller size than it actually is. For example. The image size is 1024 x 640. When I open it in illustrator it is 240 x 140. Why does Illustrator open an image in a smaller size? Is it a setting or is this normal in illustrator?

Thanks