[robski]

Originally Posted by john20d

Hi, as I understand it only the Canon 1.4 converter will allow AF, enjoy the lens, can't wait to see some results, John
P.S. My information came from Jessops when I enquired about the same lens.

Another case of wrong information given out by Jessops.

More to do with the camera body. 20D,30D,350D and 400D has a AF limit at f5.6 so your have to do the tape trick to maintain AF. I think your find the 1D bodies have a limit of f8 so it would take the 400 f5.6 + x1.4 and still AF.

For the 20D the AF working range of light is EV 0.5 - 18

For the 1D the AF working range of light is EV 0 - 18