Extension tubes and the 100mm macro

[DionM]

Has anyone tried Canon's 100mm macro with a set of tubes? How does the AF perform? Any other comments? Handling - do you need the tripod ring?

[gasrocks]

Yes, tubes work great. Autofocus? In macro you shouldn't be using it. Tripod collar (and a tripod) are almost mandatory. If you already have the 300 4 IS L lens (which comes with a tripod collar.) You can get a $25 part from Canon (an adapter = plastic sleeve that fits inside the collar,) that makes it work on the 100 macro. Saving you from buying another collar for $140.

[SDK^]

Autofocus won't work with the tubes and you will also lose a number of stops depending on how long the tube is.

I have the Kenko 12, 20, 36mm set and when using the 36mm or combined tubes you do lose a couple of stops and depth of field is vastly reduced.