>>2949807Yep, it's pretty bad at 100%...
The actual flaws of this lense are minor spherochromatism, and quite strong coma, which of course goes away on stopping down.
In comparison to other vintage 50mm's it is simply dominant when it comes to contrast and resolution, even at 1.2, as compared to their 1.4, 1.8, 2, 2.8, etc.