That's interesting. The zuiko glass has good overall contrast but the difference is quite noticeable. I've been shooting on Olympus glass for a while (OM and MjuII) but now have some Zeiss lenses to play with. They are as yet unused but I'm hoping for 'the look'.
1,2 and 4 are from the Hexar, the other 2 from mju ii. Cheers