My question is: I've just bought a Canon Extension Tube EF 12 II. I have a 60D and a EFs 17-55mm . But, when mount the Extension to the lens, it does not focus at all! I cannot get any focus, no matter the distance. But, I get the extension tube working all right with a 75-300 lens. And yet, Canon says the this extension works ok with this lens.
Please, any idea about what's going on?
Paulo Roberto (Brazil)