pdfpage

NSImage -> PDFPage -> NSImage how do I mantain resolution?

I have a bunch of NSImages that I'm keeping in a PDFDocument, as PDFPages. When I insert the NSImage the first time, the size of the NSImage is in points (72 dpi), and the size of the (only) NSImageRep is in pixels (200 dpi). However, the NSImage that I get out of the PDFPage has 72 dpi for both image AND imagerep. How do I recover my...