blurry vision is used to indicate your health-level so the screen is supposed to get blurry when hit by any kind of attack. if your vision is blurry when you join a server it is most likely, that your character is not on maximum health. the actual bug would be that you can clear is up by going to video settings.

on how to restore health i would recommend to watch this video
http://www.youtube.com/watch?v=Zci9FnbXoNE
the guy that made this video has made a couple other videos explaining most of what you need to know about medical stuff in DayZ

so far i have been unable to reproduce this issue on the latest experimental build.

fixed the problem by manually deleting the BattlEye folder from the
...\SteamApps\common\DayZ folder and then validating game files via steam

edit: not fixed game crashes now one or two minutes after joining the server