At first, I found the 'cron to be a bit harder to focus than the nokton. Particularly because the focusing tabs are different, and the 'cron is tiny! I just wish the tab on the nokton was on the 'cron, but once you get used to using that raised bump of concentric circles on the front of the tab, focusing is easy.
Considering I don't scrutinize image quality, I've found the nokton to be
slightly more contrasty overall. Especially when shooting into a light source or strong back lighting. The nokton
does have modern coatings, where the 'cron does not. The 'cron tends to be equally as contrasty in most situations.