I was accused to prefer Zeiss lenses to Fed ones.
So, I try to disculpate with two photos.
Frankly, the result is not so bad with this 4,5/28mm Fed...

http://www.ussrphoto.com/UserContent/2742017_Fed 28mm 1 001.jpg

http://www.ussrphoto.com/UserContent/2742017_Fed 28mm 2 001.jpg
Absolutely no correction, of course.
Amitiés. Jacques.
