I got an OD=5 solar filter for my 80 mm refractor and took a first look at the sun this afternoon. Two sunspots are clearly visible. The large spot at 3 o'clock is dirt on the camera sensor. The apparent rotation period is supposed to be around 28 days, so by taking a picture each day it should be possible to make a time-lapse movie.
To really see structure in the sun requires a very narrow (~0.7 Ångström) bandpass filter centered around the H-alpha emission line at 656.28 nm. Unfortunately these range from expensive to very expensive...
