pdfToolbox Visualizer - Visually inspect your PDF and identify potential problems

When using a preflight profile and checking PDF files for issues, there is often the question whether a possible problem flagged by the preflight check is really an issue. In addition, there are often aspects of a PDF file that cannot only be judged by the human eye.

pdfToolbox Visualizer provides the necessary toolset to inspect and judge very quickly and easily whether a potential problem is really a problem that needs to be addressed.

This lesson offers a tour through the main features of the pdfToolbox Visualizer. The freely available "Visual" page from the Altona Test Suite 1.0 (download from www.eci.org, section "Downloads") is used as a sample file.

Open the PDF file "Altona Test Suite - Visual page" in pdfToolbox

Enter the "Visualizer" mode from the main menu, or by using the keyboard short cut "Shift-Command-i"

Inspect ink coverage

Visualizer by default launches into the "Ink coverage" view.

  1. Depending on the threshold value entered (here it is the value of "300%"), Visualizer will highlight areas of the page where the ink coverage is above the threshold value.
  2. A 'temperature scale' beginning at the threshold value and 50% upwards indicates the degree to which the ink coverage at a certain page area exceeds the threshold value. As a special case, an ink coverage of 400% (or beyond) is always highlighted in pink.
  3. In some areas of the page the ink coverage goes beyond the threshold value but only in a way that will hardly cause problems on a printing press.
  4. Once the threshold though is exceeded by more than a few percent, and in a more or less contiguous area of several square centimeters, it is possible that the printing process is affected adversely. In such a case, it can be useful to apply the ink optimizing color conversion in pdfToolbox, based on a suitable DeviceLink profile.
  5. "Pink" highlighting inside the page area usually points to a serious problem - 400% ink coverage is more than most printing processes can handle. Typically such high ink coverage is the result of an inappropriate use of "Registration" color, which is normally only used for page marks outside of the trim and bleed box, for example for crop and registration marks.

The regular view

  1. Within each Visualizer mode there is always a "Regular" view - showing the full unfiltered view of the page.
    As the keyboard can be used to switch quickly between the views within a mode (as well as between modes), it is possible to toggle between a diagnostic view, for example the ink coverage highlighting, and the regular view - this makes it easy to clearly see the page content and find out what kind of objects might be causing an issue.
  2. The regular view also shows the area coverage for each colorant as well as a total for the area coverage of all colorants. This is a very reliable indicator to estimate the use of each of the colorants - an important topic in printing processes where color inks (as opposed to the black ink) are relatively expensive.

Note: Some other variations of the area coverage values can be found in the "Process separations" view and the "Spot color separations" view.

Inspect the process separations

  1. Switching to the "Process separations" view will open a view of the non-black process separations Cyan, Magenta and Yellow.
    In this view, normally no objects should show up that usually belong to the black plate only, like black text or grayscale images. If they do show up in this "CMY channels" view, this is normally a strong indicator that unwanted separations or re-separations have been applied to black only page content. In many cases such issue can be resolved by applying the Switchboard action "Correct 4c Black".
  2. The display of area coverage values in this view also indicates the combined area coverage of just Cyan, Magenta and Yellow (CMY).

View of Black plate

  1. This "K channel only" or black plate view shows only the black colorant on the page.

Typically all black text as well as grayscale images would clearly show up in this view. Toggling back between this view and the CMY view will quickly reveal whether any 'black' page objects ended up in the wrong separations.

Process separations - displayed without spot colorants

This view lets you quickly determine whether inadvertently any spot colors were converted to process.

Full color view

The full color view is available in various places - so that in all viewing modes you can quickly toggle between a diagnostic view and the 'normal' view.

Spot color separations mode

The first view of the Spot color separations view displays a view of just the spot color objects on the current page.

View spot colors together with Black plate

Especially useful for evaluating duotone images or other objects using one or more spot colors together with the Black plate.

View CMYK without spot colors

Quickly toggle between this mode and the spot color view to find out which color objects use process colors and which objects use spot colors.

Toggle between views within each diagnostic viewing mode

While in Visualizer mode, there are two ways to toggle between views within a diagnostic viewing mode:

  • use the "View" menu in the upper left of the Visualizer window.
  • use the keyboard: the "right arrow" key moves forward within the list of views as shown in the menu, while the "left arrow" key moves backward. In order to proceed to the next viewing mode, use "Cmd-right arrow", to go back to the previous viewing mode, use "Cmd left arrow".

Full color view

The full color view is available in various places - so that in all viewing modes you can quickly toggle between a diagnostic view and the 'normal' view.

View individual separations: Cyan

In the "Individual separations" viewing mode, each of the separations present in the current page can be viewed individually, showing each "plate" in grayscale (the appearance of each separation is shown in the upper right, where the total area coverage values are displayed).

View individual separations: Magenta

Same as previous step - showing the Magenta separation.

View individual separations: spot color Orange

Same as previous step - showing the spot color Orange separation.

Viewing image resolutions against a threshold value

In the same way as for images, it is possible to check the resolution of bitmaps. In the example shown here no problems are found, and a message in the document window indicates just that.

Viewing 'small objects' - small text objects

Small objects have a tendency to either not print properly, or to be difficult to see or read. Here, small text objects are highlighted on the page, threshold values are chosen through the "Usage" menu.

Viewing 'small objects' - close up through Loupe feature

Obviously, on screen it is difficult to properly see small objects in the full window document view. To close up on a specific small object on the page in the pdfToolbox standalone version, use the Loupe feature (see menu Window -> Loupe).

Viewing 'small objects' - in the Loupe, toggle between full view and diagnostic view

As the highlight color will cover up the actual small object, just toggle to the full view using the keyboard short cut "right arrow" key, and then go back using the "left arrow" key.

Viewing 'small objects' - thin lines

The "Highlight (lines)" view highlights lines that are less wide than specified by the threshold values in the "Usage" field. Please note that the threshold values for each setting differ between monochrome lines at 100% tint versus multi-color lines or lines using an intermediate tint value.

Viewing 'small objects' - close up through Loupe feature

To close up on a specific small object on the page in the pdfToolbox standalone version, use the Loupe feature (see menu Window -> Loupe).

Viewing 'small objects' - in the Loupe, toggle between full view and diagnostic view

As the highlight color will cover up the actual small object, just toggle to the full view using the keyboard short cut "right arrow" key, and then go back using the "left arrow" key.

Checking the "Safety zone" - Page objects "on the edge"

The "Page border" view in the "Safety zone" mode simply highlights an area from the trim size of the page 5mm inward. Due to less than perfect mechanical processing the actual location of the 'border' may vary a little bit. Objects close to the page border may actually end up on the border which can look very displeasing to the human eye. In this view, make sure that no important page object - especially text - is in the safety zone.

Zoom in using the Loupe tool - even in the "Safety zone" mode

I the sample document, a text test patch reaches very close to the page border. If the trimming of the page is off by 1 mm or so, the text will begin to be on the page border, not just close to it. In order to look at this at a more convenient zoom mode, use the Loupe tool (in the document window, just drag the mouse over the area of interest while holding down the Shift key - the Loupe will open and show that area enlarged).

Checking the "Safety zone" - Page objects "bleeding off the edge"

Any objects 'ending' on the page border should actually extend beyond the page border for at least 1mm or 2mm to allow for less than perfect mechanical processing. The "Bleed area" view highlights the area 'around' the page border: 3mm to the inside plus 3mm to the outside. The rule of thumb is: any page object on or very close to the page border should actually go as far as the highlighted region in this view goes.

Create a Visualizer report

In the upper right of the Visualizer view there is a button "Report..." which will create a report with all relevant Visualizer views in PDF format. For each page in the visualized PDF document, a report page will be created in the report document.

Progress bar during report creation

As the creation of the Visualizer report may take a little while (for the sample document "Altona Visua" it takes 10 to 15 seconds on a typical machine), a progress bar at the bottom of the window informs the user about the progress.

Sample of the Visualizer report

A Visualizer report page contains all the relevant views also available in interactive mode. As a Visualizer report is a regular PDF document, it can be viewed with every up to date PDF viewer, including the free Adobe Reader.

Enlarged view of a Visualizer report page

Here an enlarged view of the top part of a Visualizer report page is shown.