EDIT: EdMika no longer sells the Brass conversion mount.
Here is a link to the new "Polymer" mount he now uses: https://photography-on-the.net …showthread.php?p=16760793
I just finished converting my FDn 50mm 1.4 to an EF mount using the new EdMika Canon FDn-EOS adapter kit. http://www.ebay.ca …1438.l2649#ht_2239wt_1344
He has developed a new line of kits specifically for the Canon FDn (New FD) "bayonet" mount lenses. They don't fit the older Canon FD or FL "breechlock" lenses.
The conversion process is quite easy to do for the average person but you really should watch the how-to video first. http://www.youtube.com …k&feature=player_embedded The video is 12:21 and that is about how long it took me to do the entire conversion.
This conversion allows full infinity focus without any optics so that image quality is preserved. On a Full-Frame camera there might be mirror interferance with certain lenses at infinity focus. At closer focus distances there is no interferance, and using Liveview eliminates the problem at longer focus distances. Even if you forget and do hit the mirror, it cause no damage to the lens or the mirror. With 1.6 and 1.3 crop cameras the mirror will never hit. (Apparently 1Ds FF cameras have a smaller mirror frame and also have no interference at infinity)
The kit consists of a really nice precision machined brass mount (fitted with a black sleeve to prevent light scattering) and a small machined peice of brass that is used to engage the aperture control after the old mount is removed. The mount comes equipped with a "Dandelion" fully programable Auto-Focus confirmation chip. Also included is a EF lens cap.
Here are some photos of the lens after conversion to the EF mount. There is a small indentation for a "lens Mount Index". (mounting alignment mark). I dabbed a bit of red paint on it so it is easier to spot.