Hi all,


I'd like to get one or two extension tubes to improve the focusing distance of my lenses (mainly my 24-105 and my 70-200). I've been looking at the Kenko tubes. Does anyone know what the difference is between the two Uniplus tubes (12mm and 25mm) and the Tube Set (12mm, 20mm, and 36mm), apart from the set having difference tube sizes? Is 36mm pushing the limits of what an extension tube can do (given that Canon doesn't make one at that size)? And will I be OK with just the 25mm (potentially coupled with the 12mm)?


Thanks!


Tony