As a bird watcher with a spotting scope, I'm enticed by the concept of digiscoping with a small compact, rather than lugging round a heavy DSLR with an equally heavy lens. My result to date have been modest, "record" shots are possible but quality is indifferent.
While searching for inspiration I turned up an interesting post from Gene Smith who compared a small sensor LX3 to an bigger(4/3rds) OLY EPL1 and came to the following conclusion:_
Is Gene correct? I turn to the intellectual rigour and technical nouse of this forum for an answer."The SAME bundle of light [from a telescope]that goes into
a small optical system goes into a large optical system, that is
providing the small system can accept all of the light cone. Thus the
smaller sensor is more brightly lite, and the camera so responds. A
couple series of tests have defined why there is a problem with larger
sensor cameras. http://ohiobirds.org/forum/viewtopic.php?pid=4002