Back to the 50mm f1.8. The lens is quite small, though not pancake like small and it's all metal construction. It has a 50mm f1.4 sister lens that looks very interesting with multi-coating, but I imagine it's not easy to find one. All of the FTL lenses were never made in quantity, as it was a stopgap product.
I mounted it on the NEX-6 today and took some sample shots. I was going to do it on the full frame, but thought better of it. Too heavy and focusing is not as easy as with the NEX-6. Let's just say that I have not encountered any truly bad standard lenses. Really, it takes more effort to design a bad 50mm lens :) The lens is very sharp, even at f1.8, it's very usable, though the bokeh is not much to my liking, especially when the out of focus background has specular highlights. Stopping down to f8, it's very sharp and has good micro contrast.
Green leaves - NEX-6 & Olympus FTL 50mm f1.8 M42 @ f1.8. Click for larger.
Silhouette - NEX-6 & Olympus FTL 50mm f1.8 M42. Click for larger.
Infinity focus sample - NEX-6 & Olympus FTL 50mm f1.8 M42 @ f8. Click for larger.
Bokeh - NEX-6 & Olympus FTL 50mm f1.8 M42. Click for larger.