Wondered if anyone else has a similar issue. I've a 17-40 and a Drebel. For wide shots (landscapes or such) it really struggles to autofocus and I almost always end up on manual.
Other lenses have no trouble, including my 24. The 17-40 is OK when being used more as a normal lens. But, being used wide, even when I deliberately drop a focus point on a high contrast subject, it spends more time hunting than Dick Cheney during lawyer season.
Anyone any suggestions as to what is up?

