I have the Kenko extension tube set
http://www.amazon.com/Kenko-Auto-Extension-Canon-Mount/dp/B000U8Y88M/ref=sr_1_2?ie=UTF8&qid=1307414686&sr=8-2
Paired with my 50mm lens, I can get some fantastic close up shots. I wanted some with auto-focus and electrical contacts so I wouldn't lose all of the intelligence of the camera, although it is much more expensive to have it. overall, using a lens I already had with these comes out better than buying a 100mm macro lens that I'm not sure if I would use regularly.
http://www.amazon.com/Kenko-Auto-Extension-Canon-Mount/dp/B000U8Y88M/ref=sr_1_2?ie=UTF8&qid=1307414686&sr=8-2
Paired with my 50mm lens, I can get some fantastic close up shots. I wanted some with auto-focus and electrical contacts so I wouldn't lose all of the intelligence of the camera, although it is much more expensive to have it. overall, using a lens I already had with these comes out better than buying a 100mm macro lens that I'm not sure if I would use regularly.
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