If  "widen" = decrease the focal length then i think there are... only really seen them for camcorders tho. You are looking for something which says 0.45x or something below 1x as far as i am aware.  Cant help other than that as i havent really looked into it.

Gut reaction would be that the quality wouldnt be that great... but then all these extenders etc are compromises for buying the real deal.

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In every stone sleeps a crystal.
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