Jim, take a look at Peter"s corrector. It does an excellent job at f/3.7.... http://www.users.bigpond.com/PJIFL/page14.html Looks pretty easy to make but should be AR coated for best results... Greg Jones http://home.comcast.net/~dac20/dac_001.htm _______________________________________________ ATM mailing list http://www.atmlist.net/