3 Replies Latest reply on Jun 13, 2011 11:17 PM by Dave Merchant

    What does 100% zoom (actual size) represent?

    emil emil Level 4

      I'm asking this question because I received a pdf file with several pages representing pages of a web site. Referring to this pdf I have to create a logo with a size that should not be scaled when the logo is used for the web page. I don't know how the pdf was created and  I can't easily find out this but I'm assuming the images of the web pages used in the pdf were not scaled (interpolated). If so, does 100% zoom in Acrobat fits 1 pixel from the image to 1 pixel on screen like in Photoshop or is it like Illustrator which assumes some screen resolution that has nothing to do with the actual monitor resolution and basically 100% zoom means nothing?

      Also is there a way to extract all images used for the creation of the pdf. I tried Advanced > Image Processing > Export all Images but although it exported some images and even elements behind images like drop shadows, it didn't export all images.

       

      I will greatly appreciate your help

        • 1. Re: What does 100% zoom (actual size) represent?
          Dave Merchant MVP & Adobe Community Professional

          PDF pages are physical objects with dimensions in points (72ths of an inch) - there is no concept of a "1:1 pixel scale" for a page and you can have many objects on a single page with different dpis (plus a mix of raster and vector objects).

           

          "100% scale" in Acrobat and Reader is a physical scale representation using the OS definition of the pixels per inch on the monitor. As hardly anyone has a monitor with a physical scale correctly set, it's usually just a vague approximation.

          • 2. Re: What does 100% zoom (actual size) represent?
            emil emil Level 4

            So, it is not possible to find out the pixel dimensions of raster images in a pdf document? In fact I don't know if access to all images is even possible. As I said, I tried export and it didn't exported all images that I can see.

            • 3. Re: What does 100% zoom (actual size) represent?
              Dave Merchant MVP & Adobe Community Professional

              In Acrobat Pro, choose Tools > Print Production > Preflight.

               

              Select any check (it doesn't matter) and press the "Analyze" button - not the "Fix" button.

               

              In the results tree which then appears, open "Overview" and "Images" to see a list of every raster object in the file, with details of size, color space etc. If a graphic on the page isn't in that list it means it's a vector object.

               

              Alternately, open the PDF file using Adobe Illustrator.