Bruce, thanks for posing that question... and Brian, thanks for responding to it. I have read that the wartime Zeiss Sonnar f1.5 lenses were a kind of peak in Zeiss's design and construction, but that (if true) might only be in relation to what Zeiss had issued in the pre-war years. I have a wartime Sonnar, from the 272*** serial number batch, that once belonged to Leica Tom on this forum. And while I don't usually shoot at full aperture, and don't do studio work like Bruce, it's a lens quite capable of subtlety in capturing an image.
I think I've posted this photo before, but it's what I have in mind...
Listening by
Steve Macfarlane, on Flickr
I've mainly used this lens for landscape work...
Beach in winter by
Steve Macfarlane, on Flickr