I planed to improve the 50mm enlarging lenses at a community darkroom where I instruct. Using f/8 and projecting to 7x10.5 inches, I checked center against edge. I found little difference between the Schneider Componar (3 element) vs my Leitz Focotar f/4.5. A new Fuji f/3.5 was a tad behind. I'm surprised at the results but it was at f/8.