By manually do you mean you used Acrobat? That is the way to do it but I'm baffled why that should triple your file size. You could try with a standard PDF and see if that makes a difference.
Another way to do it is to have another Indesign doc in the appropriate orientation that you place your original Indesign document into. It saves you doing it manually in Acrobat but is still an extra step.
I am not certain if it is Acrobat. It is whatever app opens at the end of the Export process. The Mac OS-X app name is "Preview"; "About" shows v. 5.0.3 (504.1) © 2002-2009, Apple Inc.
In Preview, the maneuver is to execute Tools | Rotate Right (Cmd - R). Just learned that I can select all and rotate together, big help. Then save.
Trying to avoid the extra effort of maintaining a parallel version of the end result. Believe the manual effort, now greatly simplified, is preferable to that.
Calendar will not grow much larger; believe my 10 MB pdf is workable. Will stay alert for other space savers. Thanks for your help.
If the App says "Preview," you are uisng Apple's own Preview application built into the OS, which is probably about the worst possible thing you couold be doing to a PDF of any sort of complexity. Preview simply is not capable of working properly with PDF.
PDF prepared for print is usually very different from that meant for online viewing. You can use it, but it often is much larger than convenient for downloading, and may be stripped of interactive features that can't be reproduced on a press. Acrobat Pro, the correct application for editing PDF (and bundled in the Creative Suite packages or available as a standalone) will allow you to do your page rotations, as well as combine and arrange pages from multiple PDFs, and to optimize the size by changing the image compression, flattening transparency, and discarding user data that may not be important for online viewers.
That said, I think you really are better off making two files, and as Stix has suggested placing the pages from the two PDFs into the new file the way you want them to appear. You can use the Page tool in CS5 or 5.5 to reduce the page height of a tall document to half to hold the front or back cover if your calendar is one that folds and is stapled in the center.
Thanks. It is in fact a different file, but the inDD s a descendant from the same source file (with covers added), thus simplifying updates etc. Preview app opens by default on conversion. Will move toward Acrobat as you suggest.