1988/08/21, 07:45 UT, CM=281 Mansfield, Oh, 31-inch f/7 reflector 340x - 500x
Seeing 9 of 10. Warren Rupp Observatory. Great seeing, best I've ever seen. Split in polar cap first seen at 500x, then at 340x. 9-inch mask on and off. No moons.

For the full story, see:
http://ladyandtramp.com/weblog/channels/mars_1988/images/1988-08-21-rdb.jpg