Zoom: InDesign 100% does not equal PDF...

I'm applying for a job and part of the application involves creating a PDF portfolio designed to be viewed on screen (not print) showing a collection of artwork I've created.



I have composited each page as a 72 pixels/inch (screen resolution) A4 (international paper sizing) PhotoShop Document, and have placed each page into an A4 InDesign document. Everything looks right in InDesign - at 100% zoom all of my pages look perfectly sharp and clear, exactly how they should be.



The problem occurs when I export my document as a PDF - Acrobat's version of ''100% zoom'' Is considerably larger than InDesign's, and all of my pictures have been enlarged and appear blurry and pixelated.



Why?



Is it possible to tell a PDF document to display at a specific pixel-width; for example, 100% zoom is exactly 595 pixels wide?



If I hand in a blurry portfolio I'll never get the job! I need to find a way to make the PDF display correctly. I need to make a PDF that displays at the same 100% as InDesign.



How?



Being a job app this is quite urgent, I'd greatly appreciate any help anyone can give!
Zoom: InDesign 100% does not equal PDF...
UPDATE:



Through trial and error I've discovered it seems to work when the images I place into inDesign are 110dpi, as opposed to 72.



110 pixels/inch seems to be what Acrobat considers 100%?



Can anyone confirm and/or explain this? I'm confused as hell...



UPDATE 2:



A clue! I found in the acrobat prefferences menu that you can actually set the dpi to whatever you like - and mine is currently set to 110.



This still poses a problem for me, however, as I don't know what dpi the end-user's computer will be set to.



Is there anyway to make a document override the user's dpi setting?



I want my document to force the end user's copy of acrobat to view it in 72dpi, so that I can rest assured they'll view a crisp image at 100% zoom.



Can I do this?
Zoom: InDesign 100% does not equal PDF...
InDesign considers 100% to mean 1 screen pixel equals 1 point. I'm not sure what Acrobat is doing.



You can control the initial page view zoom level when the PDF is opened, but you can't force a screen resolution, so you are probably better off either forcing the view to fit the entire page or using high resolution images. If this is a ''for screen'' presentation, the viewer probably expects to see some pixels at large zoom levels.



Peter