Now I remember how stupid it feels to be a total n00b.
Well, I upgraded from K20 to K7 and what a great step it was.
But now recently I found myself in desperate need of DOF-preview and it takes a preview picture. On K20 it was pssible to have it step down the lens to selected aperture and view it directly through the viewfinder. And I'm absolutely certain that the option is there in the K7, too.
The question is - where?!?
I've searched through the menu and managed not to find it. Damnit. Need help.