There is an article where the author did some tests and found that 2-element diopter lenses produce better quality images than do extension tubes.
http://people.smu.edu/rmonagha/mf/diopter.html There is a rebuttal to the test on the same page, so opinions may still vary. Personally, I plan to buy diopters but only because I would be using it on a zoom lens and I have read John Shawn and others state that zoom+extension = hard-to-use * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
