Ryan Shaw wrote ----->??Unless you have a camera lens with an aperture value of
f/2.8 you had better plan on manually focusing your lens with a 2x
teleconverter.? With the Canon 7D, 40D, 50D etc... you cannot auto focus any
lens unless its maximum aperture is f/5.6.? <---


Today ?I was at Kenmore Camera asking about teleconverters.?? The person at
Kenmore told me that the maximum?aperature for auto focus to work is 4.0 or 4.5
(I forget which), which is why I did not buy one to couple with my? 7D + 100-400
zoom, which?has a maximum aperature of 5.6 at the 400mm setting.

He also told me that Canon's lens factory was heavily damaged during? the recent
earthquake, which is going to delay?deliveries of current production lenses and
postpone production of recently announced new?lenses. ?
Bill Anderson; Edmonds, WA.