How do you use Canon lenses with the OMD EM5 body?

You use an adapter. Which one depends on if you are talking about the autofocus Canon EF (EOS) lenses or the older manual focus Canon FD lenses. The EF lenses are a little bit more difficult to work with since you'll have no way to control the aperture (although there are some workarounds).

Do you have a particular lens (or lenses) in mind?

By the way, this post would probably be better in the Adapted Lenses forum. This particular forum is primarily for questions directed at the retailer B&H.

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If you look on EBay you can find adapters that have an aperture built in that you can use with EF lenses. I have one and it works very well. You simply set the lens to max aperture and the use the adapter to set the aperture to anything smaller.

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