Can anyone explain how a cheap lens i have bought http://www.amazon.co.uk/gp/product/B00333710S/ref=oh_details_o02_s00_i00 works fine on my Camcorder and any a couple of lenses on my GH2,I tested the resolution on a chart and there is no loss,the proper extender made and sold for my cam costs over £300 stirling.As it is mainly for the cam i have step up rings for the micro lenses i want to use with it.