Preview zoom doesn't remain when paging

Hello. Using Lion, latest update, on a MacPro, when reading a multi page pdf in Preview (full screen or no) and zooming it to a certain size (using either cmd-0 or cmd+/-), that zoom is ignored when paging up or down and reset to what would be a "Zoom to Fit", all this independent of whether displaying single page or two pages and whether the document is larger or smaller that the screen (in full screen) or window, independent, too, of any setting in Preview's preferences.
Is there any way to correct this?
Thanks a lot.