The Compare File function can find the differences between different working files. Differences include visual differences (differences of shape, brightness, position, and color) and ink differences. Page size and layer differences are not included. Visual differences are highlighted in the preview window. Ink differences are mentioned in the message after the comparison between working files are finished.

Comparison function

To compare working files:

  1. In the preview window, click Update.
    The current Illustrator file will be displayed.
  2. Select Compare File.
  3. While in the Preview window, use the Target File dialog to find and select the document that you want to compare to the current document.
    This will be referred to as the compared file.
    Note: The compared file does not need to be opened in Illustrator. It only needs to be selected in the Target File dialog.
     

Use one of these three methods to compare the current file and the compared file:

Method 1: Compare directly, without setting coordinate origin.

Method 2: Compare by setting coordinate origin (origin point).

  1. In the Display section of the Preview window, select the current file and set the coordinate origin by dragging the cross line from the left top of ruler to the location of the coordinate origin (the cross line can snap to path or anchor point).
  2. In the Display section of the Preview window, switch to the compared file and set its coordinate origin in the same way.

Method 3: Compare by setting coordinate origin and contrast area.

  1. Select the current file and set the coordinate origin by dragging the cross line from the left bottom of ruler to the location of coordinate origin (the cross line can snap to path or anchor point).
  2. Set the comparison area by clicking  and then drawing a contrast area in the preview dialog box.
  3. Switch to the compared file and set its coordinate origin in the same way. 
    The rectangular box will locate in the corresponding area automatically.
  4. Delete the box and draw the second rectangular box.
     This button can help to delete it if you don't want to do area contrast.

Ink Match function

Ink Match function helps you to compare inks in two files by identifying the same ink.

  1. To display the Ink Match window, select Ink Match from the side menu in the Preview window.


  2. From the compared file, set the proper ink.
    Tip: It is more convenient to match inks to the Current document when ink quantities are different because the Current document may already be prepared for press.
  3. To confirm ink match, click OK.
    The image below illustrates the comparison after applying the Ink Match function.
       

  4. Set the resolution while the working files are compared.
    The default resolution is 72 dpi, ranging from 72 dpi to 9,999 dpi. Setting a lower resolution will be faster to compare files than using a high resolution, but it is less precise and some small differences may not be shown at lower resolutions.



  5. Click the Execute button.
    The differences between the two files will be displayed in the preview window.


  6. To save the preview window in PDF format, click Print Screen.



  7. Number of Difference displays the total number of different areas between the two working files compared. 
  8. While comparing the files in the preview window, you can use these tools:

    Mark different areas

    Mark Difference marks the areas where the current working file and the compared file differ.
    When    is in open mode (the default), the "mark" is displayed in the preview window.
    The default width of the lines of the mark box is 2 pt. Each mark has a number to identify the difference. The default number size is 12 pt.

    Fill different areas

    Fill Difference can highlight all pixels in the different areas between the two working files.

    When    is in open mode (the default), "different areas" are displayed in the preview window.

    Show which file is being displayed compared

    When    is in open mode for View Compared Document, the compared file is displayed. When    is in open mode for View Original Document, the original file is displayed. They cannot both be displayed at the same time.

  9. Color to use for Difference allows you to define the colors for Mark Difference and Fill Difference. Both will share the same color. The default color is red (C0% M100% Y100% K0%).
    Change the color by double-clicking the color plate, select a new color in the color dialog box that appears, and click Yes.

View mode

Working files can be compared in all modes. During the comparison of working files, all view modes are applicable. When the normal image is previewed by color or in positive or negative format, the color of "marks" and "different areas" keeps consistent to the complete color plate. All the differences of color plates are marked. The number of different areas include all the differences of the two working files.

This is the view of the normal image in single color under Comparison if the preview of the normal image in single color under Comparison function.

This is the Preview image when the object inside of the current red border is shown.