Canon FD lens on EOS body

I have some old FD lenses and I'd like to use these lenses on my Canon EOS 60D.
Few days ago I bought an FD/EF adapter, and I take some photos with a Canon FD 28mm/2.8 and a Canon EF 17-85mm lens.
The adapter contain a small correction lens. It magnifying the picture - unfortunately the quality is poor.
Lets see the quality! I take all photos in RAW, cut the center and upper left part and pasted the pictures in one image.
You can see on the left side the FD lens resolution in aperture 5.6 and 16, and the EF lens on the right side.
The adapter has a large distortion away from the center.