This galaxy is a classic in just about any size instrument, provided you have access to dark skies. The Sombrero galaxy (Messier 104) lies some 40 million light years distant and is named for the appearance that comes about from a dark lane of dust that cuts lengthwise across the galaxy. This is a spiral galaxy seen nearly edge-on. The vast lanes of dust in the spiral arms can be seen as a dark line, cutting the galaxy in two lengthwise in even a 6" scope. In this size scope, the galaxy will often take on the appearance of being cut off sharply on one side, rather than split down the middle, depending on the visibility the southern bulge.
Smaller scopes will show a slightly irregular shape, with hints that there is something more here than a simple elongated fuzzy. Larger scopes will show the dark lane clearly. In any scope look for a bright, nearly stellar core, and large hazy bulges to the north and south. The east/west edges of the galaxy often take on the appearance of two sharp spikes.