I have found that the S&S ring that fits the Tokina 10-17 fits but I needed to add a 1/2" rubber band to the barrel to make it nice and snug. The S&S gear says it is for a "Cannon EF 16-35mm F2.8L USM Zoom Gear". Also have a F.I.T. gear for the "Tokina 10-17mm" that is same I.D. but not quit as long. Between the two I prefer S&S on the 17-70. Think it would work for you.
Thanks for this. I an using the lens but don't have a prober zoomgear for it. I will try this ríng and adapt it for the lens.
Ths lens is ok and I use it with the compact dome port.