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Message: <blockquote data-quote="JGobeil" data-source="post: 3282283" data-attributes="member: 24649">I made a TN using the 2 bottom lens assemblies shown in the last photo of my post of yesterday.They are almost a perfect fit for the cheap M43 extention tubes found on eBay.  The fit is perfect at the camera end and just a bit of grinding with a Dremel with sand paper make it a tight fit at the other end.The length is perfect when the extension tube is made of a only a 14mm center tube with the 2 bayonnet ends.  I measured 1.33X, a bit low for my taste, so I added a 7mm center tube to spread the 2 lens assemblies and it is now 1.42X, just what I wanted - a rubber spacer kept everything in place.Paul measured 1.8X for his TN made from the same lens so he probably didn't use the same lens elements or a different assembly.Quick tests seem to show sharp images without CA.</blockquote>