Some time ago I saw a deep enhanced Schmidt plate by David Malin showing never before seen faint extensions surrounding The Sombrero galaxy M104 with a faint tidal stream also visible.
Could these faint features be extracted from the 210min of data I had taken recently using a modern sensitive CCD and 6" telescope...?...the answer is
YES 
http://www.pbase.com/strongmanmike20...73938/original
I was amazed to see the tidal stream loop below and slightly to the right of the galaxy. Tidal Streams are the faint remains of long ago torn apart companion galaxies.
The superimposed normal shot of M104 gives an idea of just how far reaching these faint features are.
I would estimate the surface brightness of the faintest extensions visible to be somewhere around 28mag/square arc sec perhaps..?
Click on the image to see the rest of the "normally" processed image versions.
I had managed to reveal similarly faint details around Centaurus A but that was with 15 hours of data collected from a perfect dark site, to me being able to see similarly faint details in just 3hrs worth of data taken through a 6" telescope from semi rural skies is really quite incredible
.
Deep Cen A:
http://www.pbase.com/strongmanmike20...08746/original
Mike